NEWBuildS WORKSHOP 2014 - newbuildscanada.canewbuildscanada.ca/.../01/NEWBuildS-Workshop-2014... · 5 Alex Cheng University of British Columbia 50 Hans-Erik Blomgren Arup, USA

NSERCSTRATEGICNETWORKONINNOVATIVEWOODPRODUCTSANDBUILDINGSYSTEMS

NEWBuildSWORKSHOP2014

May7&8,2014

Vancouver,BC

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NSERC Strategic Network on Innovative Wood Products and Building Systems (NEWBuildS)

Wood Science and Technology Centre University of New Brunswick 1350 Regent Street Fredericton, New Brunswick CANADA E3B 6C2 Tel: (506) 453-4507 Fax: (506) 453-3574

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www.NEWBuildSCanada.ca

May 7th, 2014

Foreword:

Welcome to NEWBuildS Workshop 2014!

On behalf of NEWBuildS, we would like to thank you for taking the time and interest

in attending the Tall Wood Building Design Project Workshop (May 7th morning) and

the 4th NEWBuildS Annual Workshop (May 7th afternoon and May 8).

This document contains abstracts for the presentations at these two events. These

presentations cover the analysis and design of a 20‐storey wood‐hybrid building and

the research work of over 30 graduate students and Post‐doctoral fellows, addressing

a broad range of topics related to performance of wood building products and

systems.

We hope at the end of the Workshop you will feel that your time is well spent. We

would encourage you to visit our web site www.NEWBuildSCanada.ca to get more

details on the operations, events, research program and research output of

NEWBuildS.

Thank you.

Dr. Y. H. Chui Kenneth Koo, P.Eng, P.E. Scientific Director Network Liaison Manager NEWBuildS / UNB NEWBuildS / FPInnovations

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Table of Contents Page #

Foreword 2

Table of Contents 3

Partner University, Network Partners & Funders 5

Attendee List 6

Exit Survey 8

TALL WOOD BUILDING DESIGN PROJECT PRESENTATION (May 7 morning) 9

1. The use of wood as a main building element in tall buildings 10

2. Building Envelope for a Tall Wood Building 11

3. Lateral load resisting system for the tall wood building 12

4. Gravity load resisting system for the tall wood building 13

5. Fire risk comparison of the demonstration building with a comparable non‐combustible building 14

6. Fire Resistance of Structural Elements and Fire Safety During Construction 15

NEWBUILDS WORKSHOP 2014 (May 7 afternoon) 16

Session 1: Structural Str 1: Stability of CLT Wall Panels Subjected to In‐plane Gravity Loading 18

Str 2: Force Transfer Around Openings in Walls Subjected to In‐plane Loading 19

Str 3: Innovative Post‐tensioned CLT Walls 20

Str 4: Nonlinear Dynamic Analyses of FFTT Timber‐steel‐hybrid system 22

Str 5a: Practical Height Limits for Tall Timber Buildings 23

Str 5b. Capacity surface of hybrid timber buildings under uni‐ and bi‐directional seismic excitations 25

Session 2: Connection Behaviour CB 1: Localized Rolling Shear Reinforcement of CLT Systems 27

CB 2: Continuity Connections for CLT Plates in Hybrid Superstructures 28

CB 3: Connections in CLT Building Systems 29

CB 4: Development of an Innovative Hybrid Timber‐Steel Moment‐Resisting Frame

for Seismic‐Resistant Heavy Timber Structures 30

CB 5: Development of Novel Connection Systems for CLT Infilled Steel Moment

Resisting Frames 31

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NEWBUILDS WORKSHOP 2014 (May 8)

1st International Keynote Speaker: HIGH‐RISE TIMBER BUILDINGS IN EUROPE – PROJECTS, CHALLENGES, SOLUTIONS AND FUTURE DEVELOPMENT Dr. Dr. Stefan Winter, Technical University of Munich 32

Session 3: Fire Performance FP 1: Fire Risk Analysis 34

FP 2: Rationalization of Life Safety ‐ Code Requirements for Mid‐rise Buildings ‐‐‐

FP 3: Fire Behaviour of Cross Laminated Timber Panels 35

FP 4: Fire Performance of Timber Connections 36

Session 4: Acoustics & Vibration A & V 1: Innovative Ways to Make CLT Panels Sound Absorptive 37

A & V 2: Technique for Simultaneous Measurement of Elastic Constants of CLT Panel 38

A & V 3: Vibrational Performance of CLT Floor 39

2nd International Keynote Speaker: BUILDING ENVELOPE PERFORMANCE OF WOOD‐BASED BUILDING SYSTEMS: RESEARCH PERSPECTIVE FROM THE US Dr. Sam Glass, U.S. Forest Products Laboratory 40

Session 5: Durability & Energy D & E 1: Characterizing Wind‐driven Rain Load on Mid‐rise Buildings 42

D & E 2: Developing Durable Building Envelope Assemblies for CLT Construction 43

D & E 3: Developing Durable Wood‐frame Building Envelope Systems for Net‐zero Energy Ready Buildings 44

D & E 4: Energy Efficiency of Mid‐rise Building 45

Partner Universities

Carleton University

Concordia University

McGill University

Ryerson University

Université du Québec en Abitibi‐Témiscamingue

Université Laval

University of Alberta

University of British Columbia

University of New Brunswick

uOttawa

University of Toronto

University of Waterloo

Western University

Network Partners & Funders

Alberta Innovates BioSolutions

CMHC ‐ Canada Mortgage and Housing Corporation

CWC ‐ Canadian Wood Council

BC FII ‐ Forestry Innovation Investment

NRC ‐ National Research Council

Workshop Sponsor

Structurlam Products LP

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NEWBuildS Workshop 2014

Name: Affiliation Name: Affiliation

1 Aaron Akotuah Ohene Carleton University / NEWBuildS 46 Graham Savage New Brunswick Department of Economic Development2 Adam Gerber University of British Columbia 47 Guido Wimmers Passive House3 Afrin Hossain UBC Faculty of Forestry 48 Haitao Yu Landmark Group of Builders4 Alejandro Medina Hevia Carleton University / NEWBuildS 49 Hanping Hong Western University / NEWBuildS5 Alex Cheng University of British Columbia 50 Hans-Erik Blomgren Arup, USA6 Alpin Kahveci Carleton University / NEWBuildS 51 Helen Griffin Canadian Wood Council7 Andrew Harmsworth GHL Consultants 52 Henrico Rollke Still Creek Engineering Ltd.8 Andrew Wong Thomas Leung Structural Engineering Inc 53 Hua Ge Concordia University / NEWBuildS9 Angelique Pilon University of British Columbia 54 Hyung-Suk Lim University of British Columbia

10 Angelo Croce Component Consultant 55 Iain MacDonald University of British Columbia 11 Arash Azadeh BC Housing 56 Ian de la Roche DELAROCHE Consultancy 12 Banda Logawa University of British Columbia / NEWBuildS 57 Ian Hartley University of North British Columbia / NEWBuildS13 Ben Curry Halsall Associates 58 Ivan Dionne Halsall Associates14 Bert Ponce Louisiana Pacific Corporation 59 J Daniel Dolan Washington State University15 Betty Chan Public Works and Government Services Canada 60 James V Zidek University of British Columbia 16 Bill Downing Structurlam Products Ltd 61 Jasmine B. Wang Canadian Wood Council17 Bob Brown Wood WORKS! BC 62 Jeffrey Erochko Carleton University / NEWBuildS18 Bob Knudson FPInnovations 63 Jianhui Zhou University of New Brunswick / NEWBuildS19 Brad Wang FPInnovations 64 Jianzhong Gu Thompson Rivers University20 Brian Maver WHM Structural Engineers 65 Jieying Wang FPInnovations21 Bruno Di Lenardo NRC Construction - CCMC 66 Joe Chen Timber Products Inspection, Inc.22 Caleb Goertz University of British Columbia / NEWBuildS 67 Johannes Schneider University of British Columbia / NEWBuildS23 Cameron McCartney National Research Council Canada 68 Jones, Robert Natural Resource Canada24 Carla Dickof Fast + Epp 69 Joseph Su National Research Council Canada 25 Cecilia Cheung Pioneer Engineering Consultants Ltd. 70 Julie Frappier Nordic EWP26 Chelsea Olson Halsall Associates 71 Justin Seguin Brookfield Residential27 Christian Dagenais FPInnovations 72 Kelly Anderson City of Vancouver 28 Chun Ni FPInnovations 73 Ken Chow Pioneer Engineering Consultants Ltd.29 Ciprian Pirvu FPInnovations 74 Ken Lau Ainsworth Engineered Canada 30 Colin Chornohus Structurlam Products Ltd. 75 Kenneth Koo FPInnovations31 Conroy Lum FPInnovations 76 Kevin Below Douglas Consultants32 Coralie AVEZ UBC Faculty of Forestry 77 Kevin Cheung Western Wood Products Association33 Dave Cleverley Intelligent Wood Systems Ltd, Scotland 78 Leah Bradford-Smart Still Creek Engineering Ltd.34 Dave Gardner Structurlam Products Ltd. 79 Lillian Mah Mnemosyne Architecture 35 David Lyall Simpson Strong-Tie Canada 80 Lydell Wiebe McMaster University36 Denisa Ionescu BC Housing 81 Lynn Embury-Williams WoodWorks BC 37 Dustin Willms Fast + Epp 82 Ma Siyao University of British Columbia / NEWBuildS38 Ebenezer Ussher University of New Brunswick / NEWBuildS 83 Maik Gehloff Gehloff Consulting Inc.39 Edmond Lim LimTek Solutions Inc. 84 Maria Stefanescu Boise Building Proucts40 Enrique Gonzalez Barillas University of British Columbia 85 Marjan Popovski FPInnovations41 Eric Karsh Equilibrium Consulting 86 Mark Clark Momentive42 Florencio Bautista WHM Structural Engineers 87 Mark Robertson Halsall Associates43 George De Ridder Associated Engineering BC 88 Mark Roozbahani City of Vancouver44 George Hadjisophocleous Carleton University / NEWBuildS 89 Masoud Sadeghi Sheikhtabaghi University of New Brunswick / NEWBuildS45 Glen Webb Decision Point North Consulting 90 Matiyas Bezabeh University of British Columbia / NEWBuildS

researchersdesignersproducersRegulators

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NEWBuildS Workshop 2014

Name: Affiliation Name: Affiliation

91 Meho Karalic K1-Engineering Ltd. 136 Stefan Winter Technische Universität München (TUM) 92 Meng Gong University of New Brunswick / NEWBuildS 137 Stephen Tolnai Structurlam Products Ltd.93 Mengyuan Chen University of Toronto / NEWBuildS 138 Stephen Yang Western University / NEWBuildS94 Michael Fairhurst University of British Columbia / NEWBuildS 139 Steven Kuan Forestry Innovation Investment (BC FII)95 Michael Fox University of Waterloo / NEWBuildS 140 Sukh Johal Wood WORKS! BC 96 Michael Kascak Structurlam Products Ltd. 141 Susan Gagnon Coast Forest Products Association97 Michael O'Reardon ICC - ES, Alabama 142 Susana Chui Pioneer Engineering Consultants Ltd.98 Michael Tait McMaster University 143 Sylvain Ménard University of Quebec, Chicoutimi99 Michael vander Laan City of North Vancouver 144 Takahiro Tsuchimoto Research Engineer, Japan

100 Mohammed Nadeem Adi University of Alberta / NEWBuildS 145 Tanzia Sharmin University of Alberta / NEWBuildS101 Moniruzzaman, P.K.M. University of British Columbia / NEWBuildS 146 Ted Szabo Alberta Innovates Bio Solutions102 Morgane Kerouedan Visiting scholar, France 147 Teresa Lowe Mnemosyne Architecture (MA)103 Murray Hodgson University of British Columbia / NEWBuildS 148 Thomas Tannert University of British Columbia / NEWBuildS104 Nichole Wapple Halsall Associates 149 Tianyi Wu University of British Columbia 105 Nick Nagy Certiwood 150 Tim Ryce City of North Vancouver106 Oliver Lang LWPAC 151 Tobias Fast University of British Columbia107 Oscar Faoro Wood WORKS! BC 152 Torsten Ball Halsall Associates108 Phil Vacca LP Corporation 153 Trevor Trainor University of Waterloo / NEWBuildS109 Ping Cheng ICC-ES, California 154 Trisha Wilbur Western University / NEWBuildS110 Randy Minaker City of Port Coquitlam 155 TzuHsien Shih University of British Columbia / NEWBuildS111 Randy Pratt Adera Capital Corp 156 Uzzwal Kumar Deb Nath Concordia University / NEWBuildS112 Ravinder Hans Halsall Associates 157 Victoria Janssens WHM Structural Engineers113 Riasat Azim University of British Columbia / NEWBuildS 158 Vincent Chiu Concordia University / NEWBuildS114 Richard Lau Pioneer Consultants 159 Wael El-Dakhakhni McMaster University115 Rick Munn Mitsui Homes Canada 160 Werner Hofstätter 116 Robert Drew Perkins+Will 161 Will Preeper Mitsui Homes Canada 117 Robert Gerard Arup, USA 162 Xiao Li Carleton University / NEWBuildS118 Robert Malczyk Equilibrium Consulting Inc 163 Xiaoyue Zhang University of British Columbia / NEWBuildS119 Robert Therrien NSERC / NEWBuildS 164 Xin Nie (Jason) University of British Columbia 120 Rod McPhee Canadian Wood Council 165 Ying Hei Chui University of New Brunswick / NEWBuildS121 Rod Rempel Mitsui Homes Canada 166 Yuan Li University of British Columbia / NEWBuildS122 Roger Little Louisiana Pacific Corporation 167 Zhibin Ling University of British Columbia 123 Ron McDougall Structurlam Products Ltd. 168 Zhiyong Chen University of New Brunswick / NEWBuildS124 Ryan Gohlich Carleton University / NEWBuildS 169 Andre Morf Structurlam Products Ltd.125 Sabrina D'Ambra Concordia University / NEWBuildS 170 Jiannan Li FPInnovations126 Sai Ganesh Pai University of British Columbia / NEWBuildS 171 Michael Meszaros City of Vancouver 127 Samuel V Glass USDA Forest Service 172 Todd Beyreuther Washington State University128 Sasana Chui Pioneer Engineering Consultsnts Ltd. 173 Yurong Shen FPInnovations129 Saul Antonio Hernandez Maldonado University of New Brunswick / NEWBuildS 174 Harold Orr Harold Orr and Sons Engineers130 Sean Chew Thomas Leung Structural Engineering Inc 175 John Orr Harold Orr and Sons Engineers131 Shawn Hagan City of Port Coquitlam 176 Harold Orr - other Harold Orr and Sons Engineers132 Shawn Kennedy University of Laval / NEWBuildS 177 Jermyn Wong Associated Engineering133 Shayan Amiri Concordia University / NEWBuildS 178 Md. Shahnewaz University of British Columbia134 Sigi Stiemer University of British Columbia / NEWBuildS 179 Chunping Dai FPInnovations135 Solomon Tesfamariam University of British Columbia / NEWBuildS 180 Mireille Beaulieu University of Sherbrooke

researchersdesignersproducersRegulators

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SURVEY: Workshop 2014


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Tall Wood Building Design Project Presentations by NEWBuildS researchers

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Presentations by NEWBuildS researchers Session 2: Connection Behaviour

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Presentations by NEWBuildS researchers – Session 3: Fire Performance

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TALL W

OOD B

UILDIN

G D

ESIG

N

PROJECT P

RESE

NTA

TION

May 7, 201

4 Radisson

Hotel Vancouver Airp

ort Led by a team of professional experts, consisAng of

Mr. Robert Drew, Perkins + Wills; Mr. Eric Karsh, Equ i l ibr ium Consu lAng and Mr. Andrew Harmsworth, GHL Consultants, a group of NEWBuildS researchers has executed the analysis and design of a 20-‐storey wood-‐hybrid building using the FPInnovaAons ‘Technical Guide for the Design and ConstrucAon of Canadian Tall Wood Buildings’ as a reference document.

Objec7ves of Workshop:

Ø  To present analysis and design results on architecture, building envelope, lateral and gravity load resisAng systems, fire risk and fire protecAon.

Ø  To engage in a panel discussion with designers, specifiers, wood products producers, researchers, government regulatory bodies and associaAons.

Par7cipants: q  ConstrucAon: builders, architects, engineers q  Producers: CLT, SCL, other EWP

q  University and government researchers

q  Provincial and federal regulatory bodies q  Industry associaAons q  FPInnovaAons researchers

A]endance is complimentary, but rgistraAon is required. Please register via e-‐mail [email protected]

May 7, 2014

8:30 am WELCOME : Ms. Embury-‐Williams Chair of Board of Directors, NEWBuildS

8:40 am OVERVIEW OF PROJECT DR. Y. H. CHUI NEWBuildS ScienAfic Director, UNB

9:00 am PRESENTATION: ARCHITECTURAL DR. MOHAMED NADIM ADI University of Alberta

9:20 am PRESENTATION: BUILDING ENVELOPE Ms. Sabrina D'Ambra (presented by Dr. Hua Ge) Concordia University

9:40 am PRESENTATION: LATERAL LOAD RESISTANCE DR. ZHIYONG CHEN University of New Brunswick

10:00 am PRESENTATION: GRAVITY LOAD RESISTANCE DR. ZHIYONG CHEN UNB

10:20 am PRESENTATION: FIRE RISK MODELING MR. XIAO LI Carleton University

10:40 am PRESENTATION: FIRE RESISTANCE DESIGN MR. ALEJANDRO MEDINA Carleton University

11:00 am

PANEL DISCUSSION: Mr. Robert Drew, Perkins + Wills Mr. Eric Karsh, Equilibrium ConsulAng Mr. Andrew Harmsworth, GHL Consultants

12:00 Noon Lunch

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2014NEWBuildSWorkshop:TALLWOODBUILDINGDESIGNPROJECTPRESENTATION

Title:Theuseofwoodasamainbuildingelementintallbuildings.

Presenter:Dr.MohamadNadimAdi

Backgroundandobjectives

Todesigna tallbuildingmadeofwoodthatwouldbeappealing tobuyers, contractorsanddevelopersalike. This buildingwould be used as an example tomodify the Canadian building code for tallwoodbuildings.

Designmethod/approach

The traditional design approachwasused,wewanted tohave adistinct building that contractors anddeveloperswouldnoshyfromduetooverlycomplicatedordemandingdesign.Throughseveraldesigniterations and various discussionswith different building groups (structural, Fire safety, and buildingenvelope)wewereabletoprovideadesignthatwasvisuallycompellingwhileatthesametimecomplywithbuildingregulationsandsafetystandardsinCanada.

Summary:

ThepurposeofthisprojectwastodesignthefirsttallwoodbuildinginCanada.Throughconsultingwithexperts in the fields of architecture, civil, building envelop, and fire safety wemanaged to produce abuildingthatcomplieswiththeBCbuildingstandardswhileatthesametimesettinganexampleofhowawood based towerwould look like for future projects in Canada. The project is a 20 story residentialtowerwithwoodenstructuralelements.Itdemonstratesthatwoodcanbeusedsafelyandefficientlyasabuildingcomponentintallbuildings.

Expectedkeyoutputandpotentialimpactofresearch

The main output of this chapter was the design of the tower itself. The appearance of the building(materials, wood ratio, window ratio, and interior) was a direct result of continuous consultationsbetweenthedifferentbuildinggroupstoprovidetheplanselevationsand3DmodelsofthefirsttallwoodbuildinginCanada.

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Title:BuildingEnvelopeforaTallWoodBuilding

Presenter:SabrinaD’Ambra/HuaGe


Aproperlydesignedandconstructedbuildingenvelopeisextremelyimportantforthesuccess(i.e.durability)oftallwoodbuildings.Theirstructuralwoodenelementsmustbeprotectedfromtheenvironmentalconditions,especiallysustainedmoistureandtemperaturethatmaycausemoisturedamagesanddurabilityissues.Thispresentationdiscussesthebuildingenvelopedesignofaconceptual20storytallwoodbuildingsituatedinNorthVancouver,arainylocation.


Soundbuildingscienceprinciplesandbestpracticesareappliedindesigningthebuildingenvelopesystemsforthe20‐storytallwoodbuildings.Theselectionofmaterials,buildingenvelopecomponentsandsystemsiscarefullyconsideredtoensurelong‐termdurabilityinadditiontomeetinghigherenergyefficiency,fire,structural,architectural,andmaintenancerequirements.

Summary:

Thewallassemblychoseniswood‐framewithsplitinsulationwithaneffectiveR‐valuemeetingtherequirementsbyNEBC2011.Non‐combustiblefibercementboardischosenasthemaincladdingmaterialwith15%engineeredwoodcladding.ACLTroofassemblyisdesigned.Chapter6ofthe“TechnicalguidefordesigningtallwoodbuildingsinCanada”isusedasthemainreferencefordesigningtheconnectiondetails.


Theoutputofthisdesignexerciseisthebuildingenvelopeassemblies/connectiondetails,theirperformanceevaluation,andexperiencegainedbyworkingwithotherHQPsandprofessionalsindesigningatallwoodbuilding.

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Title:Lateralloadresistingsystemforthetallwoodbuilding

Presenter:ZhiyongChen,YingH.Chui,EricKarsh


Woodasastructuralmaterialcandatebacktomorethan5000years.Italsohasbeenusedtobuildhigh‐rise building, e.g. YingxianWood Pagoda (1056 AD, 67.31m) and Horyu‐ji Temple (603 AD, 32.25m).However,woodstructuresintheworldareusuallybuilttoamaximumof6storeysduetorestrictionbybuildingcode.Therefore,thereisstillalargepotentialfortallwoodstructurestobebuilt.

Recently,high‐riseandlargespacebuildingsarepreferredbythecustomers.Thisposesbigchallengestodesigners and as a result will bring a break‐through to the timber structures from the structuralperspective.Inthispresentation,thestructuraldesignprinciplesandnumericalsimulationmethodsforthedemonstrationtallwoodbuildingtoresistlateralloadaredemonstrated.


Inconceptualdesign,shearwallwithacoresystemwaschosenasthe lateral loadresistingsystemforthistallwoodbuilding;theverticaljointswereassumedtoyieldfirst,andtheultimatelimitstateofthebuilding isdefinedas the failureof theshearconnectorsandhold‐downs.Thestructuraldesignof thisbuilding was conducted in accordance with NBCC. Since equations to predict the behavior of the tallwoodbuildingunderlateralloadareunavailable,aseriesofcomprehensivefiniteelementanalyseswasperformed.Thestructuralperformanceofthebuilding,e.g.seismicresponseandwindinduced‐responsewasinvestigatedusingnumericalsimulationaswell.

Summary:

Theshearwallpluscoresystembuiltwithmassivepanelsandtheconnectionsystem,includingverticaljoints,shearconnectorsandhold‐downsaresuitableforthe20‐storeyhigh‐risetallwoodbuildingwithsufficient stiffness, strength and ductility. The 2D finite element modeling approach using connectorelementsisappropriatetoinvestigatethebehaviorofthestructuralaswellastheconnectionsystem,intermsof fundamentalnaturalperiod,wind‐inducedresponse, seismicresponseand failurepath,of thehigh‐risewoodbuilding.


(1) An efficient structural design method of tall wood building was established. (2) An appropriatenumerical simulation approach for tallwood buildingwas developed based on finite element analysissoftware,ABAQUS.(3)Aninnovativestructuralsystemfortallwoodbuildingwascreatedusingmassivetimberpanelsandhighperformanceconnections.

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Title:Gravityloadresistingsystemforthetallwoodbuilding

Presenter:ZhiyongChen,MinghaoLi,YingH.Chui,EricKarsh


High‐rise and large space tall wood buildings are required to resist large gravity load and generallypossessdiaphragmwithlargespan.Inthispresentation,thestructuraldesignprinciplesandnumericalsimulationapproachesforthedemonstrationtallwoodbuildingtoresistgravityloadaredemonstratedwithfocusesonaddressingtheverticaldeformationandlarge‐spandiaphragmoftallwoodbuildings.


Toavoidthelargeverticaldeformationinducedbywoodassembliesundercompressionperpendiculartograin, continuous vertical assemblies (columns and walls) were used, and as a result, the beams atspecific level were divided by columns or / and walls. In an attempt to tackle the dimensional andvibrationproblemsoflarge‐spandiaphragm,CLTroofandHBV(wood‐concrete‐composite)–VarioFloorsystem were adopted for the diaphragm system. The HBV – Vario Floor system possesses greatstructuralperformance,intermsofstiffness,strengthandvibration,andgoodacousticperformance.

Summary:

Thegravityloadresistingsystemincludingcontinuousverticalelementsandcompositedfloorissuitablefor the 20‐sotrey high‐rise tall wood building to address the vertical deformation and large‐spandiaphragmoftallwoodbuildings.The3Dfiniteelementmodelingapproachisappropriatetoinvestigatethebehaviorofthegravityloadresistingsystemundergravityload.

Expectedkeyoutputandpotentialimpactofresearch:

(1) Agravityloadresistingsystemwasdevelopedfortallwoodbuildingtodealwithissuesofverticalcompression deformation and large span of diaphragm. (2) An appropriate 3‐D numerical simulationapproachfortallwoodbuildingwascreatedtoinvestigatethestructuralperformanceundergratifyloadtaking long‐termcreepeffectundersustained loadsandshrinkage intoaccount. (3)Someconstructionmethods topartiallycompensate fordifferential shorteningbetweenadjacentverticalelementswillbedeveloped.

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Title:Fireriskcomparisonofthedemostrationbuildingwithacomparablenon‐combustiblebuilding

Presenter:XiaoLi


Buildingwithwoodiscosteffective,aestheticallypleasing,andenvironmentallyresponsible.However,inmanycountriesbuildingcodesimposeheightandarealimitationsforwoodconstructionsmainlyduetofiresafetyconcerns.AfireriskassessmentofthedemonstrationbuildingusingaquantitativefireriskassessmentcomputermodelCUriskwasperformed.Theobjectiveofthisworkistocomparethefireriskoftheproposedcombustiblebuildingwiththefireriskofacomparablenon‐combustiblebuilding.


Oneofthemajorconcernsthathinderstheadvancementandpopularityofwood‐basedhigh‐risebuildingsisthecombustibilityofwood,andthustheyarecategorizedascombustibleconstruction.Withperformance‐basedbuildingcodescombustibleconstructionsmaybeacceptedifthespecifiedperformancerequirementscanbeachievedusingcombustibleconstructionmaterials.CUriskisaquantitativefireriskassessmenttoolandisadoptedtoassessthefireriskofthedemonstrationbuilding,andthencompareitwithacomparablenon‐combustiblebuildingwhichsatisfiescoderequirements.

Summary:

Possiblefirescenariosaresimulatedonallresidentialfloors,andresultsshowedthatfireriskofthedemonstrationbuildingiscloseto(orslightlyhigherthan)thefireriskofthenon‐combustiblebuilding.Evacuationsimulationresultsshowedthatoccupantscanevacuateoutofthebuildingwithinareasonabletimeframeandoccupantevacuationtimesinthedemonstrationbuildingareshorterthanacomparablenon‐combustiblebuilding.Highreliabilitysprinklerscanpreventthefireinitsinfancy,thuscanavoidfasterfiregrowthinthecombustiblecompartmentespeciallyinthecaseofwoodpanelexposure.Inaddition,well‐designedfiredetectorandalarmsystemsshouldbeadoptedinthebuilding.Firesinextremescenariosmaycausesignificantliferisksandfirelossesthoughtheiroccurrenceprobabilitiesareverylow.However,precautionarymeasuresshouldbetakeninadvancetopreventthosefiresfromoccurringandmitigatethelossesincasetheyhappen.


Aperformancebasedfiresafetydesignapproachforcombustiblehigh‐risebuildingcouldbedevelopedthroughthisproject.ThequantitativefireriskassessmentmodelCUriskcanbeusedasantooltoevaluatethefireriskofaproposedbuilding.

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Title:FireResistanceofStructuralElementsandFireSafetyDuringConstruction

Presenter:AlejandroMedina


Currently,thenationalbuildingcodeofCanadalimitsthenumberofstoreysandfloorareaofcombustibleconstruction.Theobjectiveofthisprojectwastodesigna20storeywoodbuildingthatmeetsorexceedsthefireperformanceofanon‐combustiblebuilding.ThestructuralelementsofthisbuildingwouldbefabricatedoutofwoodsuchasglulambeamsandcolumnsaswellasLaminatedStrandLumber(LSL)panels.Ensuringthattheseassembliesmeeta2hourfireresistanceratingisessentialinorderforthistallcombustiblebuildingtobedeemedsafe.


ThesizingfortheglulammembersandLSLpanelswasfirstdeterminedbythestructuralgroup.Thefireresistanceofthesememberswasanalysedusingthereducedcrosssectionmethodinwhichonlytheunaffectedcrosssectionalareaofthememberisconsiderinstrengthcalculations.Dependingonexposuretime,thenumberofexposedsides,load,length/heightandotherparameters,thefireresistancecanbedetermined.ConstantcommunicationwaskeptbetweentheStructuralgroupandFiregroupforcaseswhereupsizingwouldbenecessarytomeetfireresistancerequirements.

Partofthestudywastoresearchthepossibilityofusingwoodcladdingontheexteriorfaçade.Afterperformingsomeresearch,itwasdeemedunsafetouse100%combustiblecladdingduetohighriskoffirespread.Acombinationofcombustibleandnon‐combustiblecladdinglimitingtheuseofwoodto30%wasrecommended.

Summary:

Thestructuralmemberssuchasbeam,columns,andwallandfloorpanelsofthetallwoodbuildingwereanalysedandtheyachieveda2hourfireresistancerating.Theexteriorfaçadewasdesignedtocontainsomecombustiblematerialwithouttheincrementalriskofflamespread.Followingrecentfirestobuildingunderconstruction,aFireSafetyPlanhasbeenputinplacetoreducethelikelihoodofafireoccurringduringbuildingconstruction.


Thisresearchprojectdemonstratedthattallwoodbuildingscanbeassafeascomparablenon‐combustiblebuildings.Theresultsofthisprojectmaybeusedbycodecommitteeswhenrevisitingcurrentlimitationsoncombustible.

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NEWBUILDS W

ORKSHOP2014

May 7

&8, 2014 Radisson Hotel V

ancouver Airport

TOPIC: NEWBuildS researchers will present researchprojects related to use of wood‐based products in mid‐riseand non‐residential construction. Projects address a range ofbuilding performance issues, including structural, fire,durability, energy and serviceability.

WHO: This workshop will bring together researchers from13 Canadian Universities and key collaborators includingFPInnovations and NRC, and other stakeholders such asgovernment officials, practicing professionals, producersand builders.

WORKSHOP PROGRAM

Day 1: May 7th

1:00 pm Welcome & Updates: Dr. Y. H. Chui / Mr. Kenneth Koo

1:20 pm Session 1 ‐ Structural

3:30 pm Session 2 ‐ Connection Behaviour

5:10 pm Day 1 adjourned

Day 2: May 8th

8:30 am 1st International Keynote Speaker : Dr. Stefan Winter, Technical University of Munich

High‐rise timber buildings in Europe ‐ Projects, challenges, solutions and future development

9:30 am Session 3 ‐ Fire Performance

11:10 am Session 4 ‐ Acoustics & Vibration

12:10 pm Lunch

1:15 pm 2nd International Keynote Speaker : Dr. Sam Glass, U.S. Forest Products LaboratoryBuilding Envelope Performance of Wood‐based Building Systems: Research Perspectives from US

2:10 pm Session 5 ‐ Durability & Energy

4:30 pm Day 2 adjourned

May 7, 2014 (afternoon)

1:00 pm WELCOME & UPDATESDr. Y. H. Chui, UNBMr. Kenneth Koo, FPInnovations

Session 1: Structural Moderator: Prof. Frank Lam

Str 1 1:20 pm

Stability of CLT Wall Panels Subjected to In‐plane Gravity Loading

PK M Moniruzzaman /Prof Frank Lam, UBC

Str 2 1:40 pm

Force Transfer Around Openings in Walls Subjected to In‐plane Loading

Sai Ganesh Pai / Prof Terje Haukaas , UBC

Str 3 2:00 pm

Innovative Post‐tensioned CLT Walls Ma Siyao / Prof Frank Lam, UBC

Str 4 2:20 pm

Nonlinear Dynamic Analyses of FFTT Timber‐steel‐hybrid system

Michael Fairhurst & XiaoyueZhang / Prof Thomas Tannert, UBC

Str 5 2:40 pm

a) Practical Height Limits for Tall Timber Buildings

Trish Wilbur / Prof. Mike Bartlett & Hanping Hong, Western University

b) Capacity surface of hybrid timber buildings under uni and bi‐directional seismic excitations

S.C. (Steve) Yang /Prof. Hanping Hong & Mike Bartlett, Western University

3:10 pm Break

Session 2: Connection Behaviour Moderator: Prof. Siegfried F. Stiemer

CB 1 3:20 pm

Localized Rolling Shear Reinforcement of CLT Systems

TzuHsien Shih / Prof Frank Lam, UBC

CB 2 3:40 pm

Continuity Connections for CLT Plates in Hybrid Superstructures

Masoud Sadegh / Prof Ian Smith, UNB

CB 3 4:00 pm

Connections in CLT Building Systems Shawn Kennedy / Prof Alex Salenikovich, ULaval

CB 4 4:20 pm

Development of an Innovative Hybrid Timber‐Steel Moment‐Resisting Frame for Seismic‐Resistant Heavy Timber Structures

Ryan Gohlich / Prof Dr. Jeff Erochko , CarletonUniversity

CB 5 4:40 pm

Development of Novel Connection Systems for CLT Infilled Steel Moment Resisting Frames

Johannes Schneider /Prof Siegfried Stiemer & Prof Solomon Tesfamariam, UBC

5:00 pm Day 1 Adjournment

5:15 pm Reception: Network researchers only

Attendance is complimentary, but registration is required. Please register via e‐mail [email protected]

1 Page 16


NEWBUILDS W

ORKSHOP2014

May 7

&8, 2014 Radisson Hotel V

ancouver Airport

May 8, 2014 (afternoon)

1:15 pm

2nd International Keynote Speaker:

BUILDING ENVELOPE PERFORMANCE OF WOOD‐BASED BUILDING SYSTEMS: RESEARCH PERSPECTIVE FROM THE US

Dr. Sam GlassU.S. Forest Products Laboratory

Session 5: Durability & Energy Moderator: Dr. Jieying Wang

D & E 1 2:10 pm

Characterizing Wind‐driven Rain Load on Mid‐rise Buildings

Uzzwal Kumar Deb Nath & Vincent Chiu / Prof Hua Ge, Concordia University

D & E 2 2:40 pm

Developing Durable Building Envelope Assemblies for CLT Construction

Sabrina D'Ambra / Prof Hua Ge, Concordia Univerrsity

D & E 33:00 pm

Developing Durable Wood‐frame Building Envelope Systems for Net‐zero Energy Ready Buildings

Michael Fox & Trevor Trainor / Prof John Straube, UWaterloo & Hua Ge, Concordia University

D & E 4 3:20 pm

Energy Efficiency of Mid‐rise Building

Tanzia Sharmin / Prof Mohamed Al‐Hussein & Mustafa Gul, University of Alberta

3:40 pm Wrap‐Up & Adjournment

Attendance is complimentary, but registration is required. Please register via e‐mail [email protected]

May 8, 2014 (morning)

8:30 am WELCOMEMs. Lynn Embury‐Williams, Chairperson, Board of Directors

8:35 am

1st International Keynote Speaker:

HIGH‐RISE TIMBER BUILDINGS IN EUROPE – PROJECTS, CHALLENGES, SOLUTIONS AND FUTURE DEVELOPMENT

Dr. Stefan WinterTechnical University of Munich

Session 3: Fire Performance : Moderator: Prof. George Hadjisophocleous

FP 1 9:35 am

Fire Risk Analysis Xiao Li & Ping Rao / Prof George Hadjisophocleous, Carleton University

FP 2 9:55 am

Rationalization of Life Safety ‐ Code Requirements for Mid‐rise Buildings

Alpin Kahveci / Prof Ehab Zalok & George Hadjisophocleus, Carleton University

10:15 am Break

FP 3 10:30 am

Fire Behaviour of Cross Laminated Timber Panels

Alejandro Medina / Prof George Hadjisophocleous, Carleton University

FP 4 10:50 am

Fire Performance of Timber Connections Aaron Akotuah Ohene /Prof George Hadjisophocleous, Carleton University

Session 4: Acoustics & Vibration Moderator: Mr. Christian Dagenais

A & V 1 11:10 am

Innovative Ways to Make CLT Panels Sound Absorptive

Banda Logawa / Prof Murray Hodgson, UBC

A & V 2 11:30 am

Technique for Simultaneous Measurement of Elastic Constants of CLT Panel

Jianhui Zhou / Prof Ying‐Hei Chui, UNB

A & V 3 11:50 pm

Vibrational Performance of CLT Floor Saul Hernandez / Prof Ying‐Hei Chui, UNB

12:10 pm Lunch

2 Page 17

2014NEWBuildSWorkshopPresentationSummary

ProjectCode:T1–9–C3 ProjectTitle: Stability of CLT Wall Panels SubjectedtoIn‐planeGravityLoading

Session#:1 Presenter:PKMMoniruzzaman


AfterflourishinginEuropeoverthepastcoupleofdecades,crosslaminatedtimber(CLT)isattractinginterestsfromNorthAmericanbuildingdesignersduetoitsattributesintermsofdesignflexibility,structuralintegrity,economicaspect,environmentalperformanceandsustainability.CLTiscomposedofcross‐wiselayersofdimensionlumber.Theyaretypicallyfacelaminatedwithapprovedadhesives.Comparedtoconventionalwoodconstruction,CLTasaplateelementhasreasonablestrengthpropertiesinbothdirectionsin‐plane.Thus,thisproductissuitableformassiveconstructiontechniquesespeciallyfortallerwoodstructures.Thepossibilityofusingthisproductwithhighaspectratiosaswallandcolumnelementsrequiresparticularattentiontothestudytheirstructuralstability.InthepresentstudythestabilitybehaviorofCLTisconsideredforastripofCLTpanelhavinganintermediatelengthunderacompressiveaxialload.

Researchmethod/approach

InordertoreceiveinformationaboutthestabilitybehaviourofCLTwallpanels,stripesofCLTpanelsasintermediatelengthmembersweretested.Then,thestabilitybehaviorwasstudiedbasedonreliabilityanalysis.ThebucklingloadofaCLTintermediatecolumnisaffectedbyalistofrandomvariables,suchas,compressivestrengthandmodulusofelasticityoflumber,endfixation,theinitiallateraloutofplumbofcolumn,andtheloadeccentricity.Inthisstudy,therelationbetweentheresponseparameterandtherandomfactorsweredeterminedbyusingresponsesurfacemethod.TheoptimizationoftheperformancefunctionwasperformedbyANOVA.Then,firstorderreliabilityanalysiswasadoptedtodeterminetheprobabilityofbucklingfailureofaCLTcolumnunderarandomload.

Summaryofresultsto‐date

ThestudyindicatedthatthecapacityofanintermediateCLTcolumnissignificantlyunderestimatedinthecodespecification.Thiscanmainlyattributedtoignoringthecontributionofthematerialperpendiculartoloaddirection.


ThescopeofthepresentstudyistoexaminethestabilitybehaviorofCLTwallpanelsbasedonreliabilityanalysis.Giventhematerial’sorthotropicbehaviorandgeometricirregularitiesanumericalmodelwillbedeveloped.Thedevelopedmodelscanbeusedinaparametricstudyconsideringdifferentloadingprotocols.Thus,thenumericalmodelcancutdowntheexperimentcostandtimeinadegree.Inaddition,themoreappropriatevaluesforthestabilityassociatedparametersinthecodewillbeproposedtomodify.

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ProjectCode:T1‐8‐C3 ProjectTitle: ForceTransferAroundOpeningsinCLTShearWallsSession#:1 Presenter:SaiGaneshSPai


Thepresenceofanopeninginashearwallleadstostressconcentrationatthecornersoftheopening.Thisinturnleadstothedevelopmentoftransferforce.Thedesignparadigmofforcetransferaroundopeningsconsiderstheseforcesexplicitlyinthedesignofshearwalls.ThisprojecttriestoassesstheapplicabilityoftheexistinganalyticalmodelsfordeterminingtransferforcetoCLTshearwalls.Also,inthisproject,numericalmodelshavebeendevelopedtoprovideinsightintothestressredistributiontosuggestsuitablereinforcementsolutions.


Firstly,theprojectfocusesonreviewingtheexistinganalyticalmodelsandtheirapplicabilitytoCLTshearwalls.Subsequently,detailedfiniteelementmodelsweredevelopedtostudythestressredistributionandtransferforcedevelopment.Differentnumericalmodelsweredevelopedtoaccountforstressdistributionindifferentconstructiontypes.Thepracticeofjoiningpanelstogetherasacoupledwalltoformtheopeningisamorecommonapproach.Forthisconstructiontype,thefiniteelementmodelwascalibratedtoexperimentaldatafromliterature.ApushoveranalysiswasperformedtostudytheperformanceoftheCLTshearwall.Theanalysissoughttohighlightthenecessityoftie‐rodsasreinforcementatthecornersoftheopening.Also,aparametricstudywasconductedtounderstandtheeffectoftie‐rodcrosssectiononthetransferforceandtheshearwallresponse.


Thereviewofanalyticalmodelshighlightedthevarianceindesigntransferforceobtainedfromthedifferentmodels.Thismotivatedthedevelopmentoffiniteelementmodels.ForaCLTshearwallwithacut‐outopening,itwasfoundthatthegluedsurfaceadjacenttotheopeningexperiencedincreasedtorsionandshearstress.Ontheotherhand,inacoupledpanelconstruction,tensileandcompressiveforcesdevelopatthecornersoftheopening.Thefiniteelementmodelcalibratedtoexperimentaldatahighlightedthenecessityoftierodsasreinforcementtominimizetheeffectofopeningonshearwallperformance.Aparametricstudyofthismodelshowedthatincreasingthecross‐sectionofthetie‐roddoesnotsignificantlyaffecttheshearwallresponse.Thisfollowsfromtheexistingunderstandingthattheshearwallresponseismainlygovernedbythewalltofloorconnection.Thetie‐rodsmainlyholdthewalltogether.


Thereviewoftheanalyticalmodelshighlightstheneedforbettermodelstodeterminethetransferforce.Thefiniteelementmodelsdevelopedhereingoalongwayinachievingthisgoal.Theprojectrevealedtheimpactofconstructiontypeonstressredistributionleadingtodifferentreinforcementrequirements.Also,thefiniteelementmodelscanbeusedinfuturetosimulatethebehaviourofCLTshearwallstocarryoutperformance‐baseddesign.Theparametricstudycarriedoutprovidesinsightintothedesignaspectsofthetie‐rodsandtheirimpactonshearwallbehaviour.

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ProjectCode:T1‐10‐T4 ProjectTitle: InnovativePost‐tensionedCLTWallsSession#: Presenter:SiyaoMa


Theresearchoriginallyaimedtostudytheself‐centeringabilityofCLTwallsbyusingpost‐tensionedtendons. The idea came from the research about the post‐tensioned timber framed system fromUniversity of Canterbury in New Zealand. In the study, they applied a self‐centering system to thebeam‐columnconnection,whichconsistsofun‐bondedpost‐tensionedtendonsandlongitudinalmildsteel bars as energy dissipative device. The post‐tensioning provided a desirable re‐centeringcharacteristic and the dissipation devices allowed adequate energy absorption by the system asshownintestingprogram.Astable“flag‐shaped”hystereticloopwasobservedwithnegligibleresidualdisplacement, confirming the self‐centering characteristics of the system. The equivalent yieldingpointcorrespondedtotheactualyieldingofthedissipationdevices.Whilethetotalmomentcapacityof the system increased with the increasing drift levels due to the elongation of the tendons, nodegradationofstiffnessandnostructuraldamagewereobserved.Theexcellentresultinspiredustoconsiderself‐centeringconceptsinCLTwallapplications.

UponconsiderationoftherelativelyrigidrockingCLTwallsystemunderseismicexcitation,theymayhaveanatural tendency toself‐centerwithout requiringpost‐tensioned tendonsprovidedadequateenergy dissipation is available to control the rockingmotion. Under seismic loads, CLTwall panelsbehavealmostlikerigidbodiesandthereversecyclicbehaviorofCLTwallpanelsisnotdegradedbythepresenceofaxialloads.Infactthesewallswithaxialloadsareexpectedtohaveincreasedinitialstiffness and shear capacity.Thevertical compressionofwalls generatedbypermanent loads (wallweightplusanyadditionaldead load),semi‐permanent loads(live loads)andtransient loads(loadsassociatedwith seismicexcitation)maybeable to resist lateral loadsand toachieve self‐centering.ThisbehaviourisexpectedwhentheaspectratiooftheCLTwallsisreasonableandthedisplacementofCLTwalls isrelativelysmallwithoutexceedingthestability limitof thesystem.So it iscritical toadopteffectiveenergydissipationdevicestocontrolthedisplacements.Consideringthesimplicityandlowcostoffrictiondampers,theresearchistodesignafrictiondamperforCLTwallsandtocontrolmovementandself‐centeringcharacteristicofthefrictiondampedCLTwallsystems.

Theobjectivesoftheresearchareasfollows:

1. AninnovativefrictiondamperforCLTwallswillbedesignedanditseffectivenesswillbestudied;

2. Developafundamentalunderstandingoftheself‐centeringabilityoffrictiondampedCLTwalls;

3. DevelopadatabasetostudythebehavioroffrictiondampedCLTwalls;4. DevelopverifiedcomputermodelstopredicttheperformanceoffrictiondampedCLTwalls;5. DevelopreliabilitybaseddesigncodeprovisionstoaddressfrictiondampedCLTwallsystems.

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Designaneffective,innovativeandlowcostfrictiondamperforCLTwalls,whichmakeitpossibleforCLTwallstoresistlateralloadsandtodissipateenergywithlessstructuraldeformationunderseismicloads;

1. Designandperformexperimentstostudythebehaviorofthefrictiondamper,whichwillhelpto refine the friction damper device and to provide necessary parameters for numericalanalysis;

2. Performnumericalanalysistostudytheseismicperformanceoftheself‐centeringCLTwalls.Inordertoshowtheinfluenceofdifferentformsofverticalcompressionsasinfluencedbytheoutofplanebendingstiffnessofthediaphragm,twomodelswillbeconstructed.BothofthemwillhavetwoconnectedCLTwallsequippedwiththefrictiondampers.Foronemodel,verticalcompressionforcewillbeloadedonthetopsurfacesofthetwowallsseparately.Andfortheother,acontinuousverticalloadwillbetransferredtothetopsurfacesofthewallthroughafloordiaphragm.


1. Theprogramhasadelaystart‐upandthestudenthasbeeninvolvedincourseworkcomponentofherstudy.

2. Designaninnovativefrictiondamper;(May31,2014)3. Manufacturethefrictiondamper.Designandperformanmechanicalpropertyexperimentof

thefrictiondamper;(June1‐Sep30,2014)4. PerformthenumericalanalysisofthefrictiondampedCLTwallsystems;(Oct1‐Dec31,2014)5. Thesis;(Jan1‐April10,2015)


1. TheinnovativefrictiondampernotonlywillbeeffectivetotheCLTwalls,butalsoprobablycanbeusedtodissipateearthquakeenergyforotherstructures.Themechanicalpropertyexperimentofthefrictiondamperwillprovideausefuldatabaseofthefriction.

2. Thenumericalanalysiswillverifytheself‐centeringcharacteristicofthefrictiondampedCLTwallsystems.Andthecomparisonofhystereticloopsofthetwomodels(describedintheresearchmethod)willindicatethebetterwayoftransferringverticalloadstoCLTwallstoachievetheself‐centeringability.

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ProjectCode:T2‐14‐C4 ProjectTitle:NonlinearDynamicAnalysesofFFTTTimber‐steel‐hybridsystem

Session#:Str4 Presenter:MichaelFairhurstandXiaoyueZhang

Backgroundandobjectives:

Aninnovativetimberandsteelhybridsystemcalled“FFTT”,consistsofmass‐timberpanelsplacedinverticalpositionalongtheheightofthebuilding,withsteelbeamspartiallyembeddedintothefaceofthewallpanelsthatrunhorizontallyateverystorey.Thetransferoflateralandgravityforcesoccursthroughthebearingofthesteelbeamsonthesolidwoodpanels.Thesebeamsalsoactastheductileweaklinksofthesystemforseismicdesign,thusprovidinga“Strong‐ColumnWeak‐Beam”failuremechanism.Animportantsteptowardstheapplicationofhybridtimbersystemsisobtainingproofthattheirconnectionsfacilitatethedesiredductilefailuremode.Forthispurpose,theFFTTconceptwillbeinvestigatedsystematicallywiththegoalsto:

1. Determinetheparametersinfluencingtheglobalbehaviourofthesystem;

2. Investigatetheinteractionbetweenmass‐timberpanelsandsteelbeams;

3. Developadesignapproachthattriggersthedesiredductilefailuremechanisminthesystem.


Tosolvethesechallenges,thecompletechainofinformationrelatedtothesystemglobalbehaviour,hybridconnectiondesign,anchoragedetailsandductilityisnecessary;startingatthemateriallevel,continuingontothecomponentlevel,tolatertransferringtheacquiredknowledgetothestructuralsystemlevel.Experimentalandnumericalinvestigationswerecombined.

First,7‐plyCLTpanelsweretestedincombinationwithwideflangeI‐sectionsandhollowrectangulartubesections.Thebeamswereembeddedintopre‐cutslotsinthepanelandheldinplaceusingtwolagbolts.Then,thecomponentwasmodelledtoallowoptimizingtheembedmentgeometry.

Inasecondstep,numericalmodelsweredevelopedtoinvestigatethedynamicresponseoftheFFTTsystemunderwindandearthquakeloading.Themodelsutilizeelementsandmaterialscalibratedtotestresultsofthevariouscomponentsofthesystemtocaptureboththeelasticandinelasticresponseofthebuildings,andaresubjectedtoanextensiverangeoflateralloadingconditions.


Theexperimentaltestsdemonstratedthatwhenusinganappropriatesteelsection,thedesiredstrong‐columnweak‐beamfailuremechanismwasinitiatedandexcessivewoodcrushingwasavoided.Subsequentnumericalmodellingallowedforcomponentoptimization.

PreliminaryresultsfromthedynamicanalysesindicatethattheFFTTcanmeetheperformancerequiredunderdesignseismicloading.Inter‐storydriftswerelowerthanrequiredandlocalplasticdeformationswerewithinareasonablerangeforlifesafetyperformanceasrequiredbytheNBCC.


ThepurposeoftheresearchistogaininsightintothedynamicresponseoftheproposedFFTTsystemandtohelpdeveloppracticaldesignguidance.

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ProjectCode:T2‐2‐C4 ProjectTitle: PracticalHeightLimitsforTallTimberBuildingsSession#:Str5a Presenter:PatriciaWilbur,S.C.(Steven)Yang,MichaelBartlett,

HanpingHong


Itiswellknownthatthedynamicresponseofastructureisdependentonitsdynamicproperties(Holmes,2007).Researchshowsthatmasstimberbuildingsperformquitewellunderseismicloads,duetotheirlowseismicweightandhighflexibility(Ceccottietal.,2010;Popovskietal.,2012).Thesesamepropertiesmayresultinastructurebeingsensitivetoexcessivewindvibrations.TheNationalBuildingCodeofCanada(NBCC)statesthatforregularstructuresmeetingcertainaspectratios,dynamicanalysisunderwindloadingisnotrequiredforstructuresunder120minheightunlesstheirdynamicpropertiesmakethemsusceptibletovibrations(NRCCanada,2010).However,preliminaryresearchindicatesthatdynamicanalysismaybeneededformasstimberstructuresexceeding44minheight(Chapmanetal.,2012;Utne,2012).Therefore,usingexistingNBCCDesignCriteriaformasstimberbuildingsmayresultinastructurethatexceedsserviceabilitylimitstates.

Thisresearchstudyaimstoinvestigatethepracticalheightlimitsoftalltimberstructuresunderwindloads,andidentifypotentialnicheareasforincreasingtheuseoftimberintheconstructionindustry,withspecificobjectivesasfollows:

‐ Identifystructuralconfigurationsconducivetomasstimberconstruction‐ Investigatepracticalheightlimitsoftalltimberstructuressubjectedtowindloads‐ Investigatelateraldeformationbehaviouroftimberstructures‐ Investigatehybridtimber‐concreteoptionsformitigatingexcessivedynamicresponse‐ Developdesigncriteriaformasstimberandhybridtimber‐concretestructures


Thisstudyfocusesonincorporatingmasstimberproductsintowell‐establishedstructuralformsandanalyzingthefundamentalchangesthiscausesinglobalstructuralbehaviour.Numericalmodelswillbeusedtoinvestigatethebehaviourofmasstimberandhybridtimber‐concretestructures.Orthotropicmaterialpropertiesformasstimberproductswillbeobtainedfromexistingliterature(Melekietal.,2010,Ashtari,2012).Comparisonsbetweenmasstimberandhybridtimber‐reinforcedconcretestructureswillbeperformedtoidentifydesignissuesformasstimberstructures.Dynamicanalysiswillbeperformedtodetermineheightlimitsatwhichstaticanalysisnolongeraccuratelycapturesthestructure’sresponse.

Summaryofresultstodate

‐ Numericalmodelsoftwostructuralforms,eachutilizingtwocoreoptions(timberandreinforcedconcrete)

‐ Capacitycurves(ULS/SLS)formasstimberstructures‐ Characterizationofglobalstructuralresponse

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ProjectCode:T2‐2‐C4 ProjectTitle: PracticalHeightLimitsforTallTimberBuildingsSession#:STR5a Presenter:PatriciaWilbur,S.C.(Steven)Yang,MichaelBartlett,

HanpingHong


‐ Detailedwindloadanalysis‐ Determinationofsuitablestructuralformsfortimberandhybridtimber‐concreteconstruction‐ Designguidelinesformasstimberandhybridtimber‐concreteconstruction‐ NBCCStaticdesigncriteriaformasstimberconstruction

References

Holmes,J.D.(2007).WindLoadingofStructures.CRCPress.

Ashtari,S.(2012).In‐planeStiffnessofCross‐laminatedTimberFloors,UniversityofBritishColumbia.M.A.Sc.Thesis.

Ceccotti,A.,Sandhaas,C.,&Yasumura,M.(2010).SeismicBehaviourofMultistoryCross‐laminatedTimberBuildings.InInternationalConventionofSocietyofWoodScienceandTechnology.Geneva,Switzerland.

Chapman,J.B.,Reynolds,T.,&Harris,R.(2012).A30levelcrosslaminatedtimberbuildingsystemandanalysisoftheEurocodedynamicwindloads.InProceedingsofthe12thWorldConferenceonTimberEngineering.Auckland,NewZealand.2012July16‐19.

Meleki,H.,I.SmithandA.Asiz(2012).Moistureinduceddeformationsinglulammembers‐experimentsand3‐dfiniteelementmodel.InProceedingsofthe12thWorldConferenceonTimberEngineering.Auckland,NewZealand.2012July16‐19.

Popovski,M.,&Karacabeyli,E.(2012).SeismicBehaviourofCross‐LaminatedTimberStructures.InProceedingsofthe12thWorldConferenceonTimberEngineering.Auckland,NewZealand.2012July16‐19.

Utne,I.(2012).NumericalModelsforDynamicPropertiesofa14StoreyTimberBuilding.NorwegianUniversityofScienceandTechnology.M.Sc.Thesis.

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ProjectCode:T2‐2‐C4 ProjectTitle: Capacitysurfaceofhybridtimber buildingsunderuniandbi‐directionalseismicexcitations

Session#:Str5b Presenter:S.C. (Steven) Yang,PatriciaWilbur,HanpingHong,MichaelBartlett


Becauseofthepotentialenvironmentalbenefitsofwoodandtheadvancesinwoodtechnologyandmanufacturing,thefeasibilityofapplyingthecompositetimbermaterialforconstructingmid‐riseandtallbuildingsisunderextensiveinvestigation.Oneoftheissuesthatneedtobeaddressedfortheuseofcompositetimbermaterialsintallbuildingconstructionisrelatedtothesafetyandeconomicsofsuchconstructionunderseismicloading,whichisinvestigatedinthisstudy.Fortheinvestigation,designedbuildingsof10storiesheightindifferenthybridmaterialsystemsareconsidered;nonlinearstaticandincrementaldynamicanalysesofthebuildingsunderseismicexcitationsarecarriedout.

Thetwomainobjectivesofthisstudyare:

Toprovideaninsightintothebalancebetweenconnectioncapacityandcapacityofthestructuralmembersandperformanceoftimber‐basedbuildings.

Tocharacterizetherecord‐to‐recordvariabilityofthestructuralresponsesandevaluatetheductilecapacityoftalltimberbuildingsbasedonnonlinearstaticpushoverandincrementaldynamicanalysisunderseismicexcitations.


Thedesigned10storesbuildings(P.C.Wilbur.,2014),whicharelocatedatVancouverB.C.,areconstructedintofiniteelementmodelsthroughANSYS,withthedetailedconsiderationofmaterialnonlinearity,especiallythewoodmaterialanisotropyandconnectionmoment‐rotationbehavior.Nonlinearstaticpushover(NSP)andincrementaldynamicanalysis(IDA)areusedtoinvestigatethenonlinearbehaviorofthebuildings.Thegroundmotionrecordsareselectedbasedonthedeaggregationofseismichazard(HongH.P.andGodaK.,2006)forVancouvertocarryouttime‐historyanalysis.TheseismicexcitationsarescaledinIDAproceduretoobtainthecapacitycurvesofthebuildingsunderuni‐andbi‐directionalseismicexcitations.


Thecapacitycurvesofdifferenthybridsystembuildings,definedbytheforce‐deformationrelationship,wereobtainedthroughNSPandIDAproceduresateachconsidereddirection.Accordingly,the3‐Dplotsdefiningthecapacitysurfacesofthebuildingshavebeenconstructedtoestimatethefailuremodesofthebuildings,andcomparedwiththoseobtainedforbuildingsofequalfootprintandheightbutdesignedusingreinforcedconcreteandstructuralsteel.Thecomparisonshowsthattimber‐basedstructureswithductileconnectionshaveaductilebehavior.Besides,thedifferentnonlinearbehaviorsofthebuildingsinstaticanddynamicanalyseswereinvestigated.Itshowsthatthecapacityandductilityofconnectionshasaninfluenceonthecapacitycurvesofthebuildings.

Page 25


Figure


Thestructuralanalysisresultswouldbeusedinfurtherstudy:

Todevelopprobabilisticmodelforthecapacitycurveunderseismicexcitations. Toestimateannualfailureprobabilityofbuildingsbyusingthecapacitycurveandthesite

specificseismichazard. Toelaboratepossibledesigncodeimplementation.

Reference

[1]. P.C.Wilbur.(2014).“PracticalHeightLimitsforTallTimberBuildings.”CivilandEnvironmentalDepartment,UniversityofWesternOntario,London,ON

[2]. ANSYSMultiphysics.Release14.5.(2013).ANSYSInc.,Canonsburg,PA[3]. Hong,H.P.andGoda,K.(2006).“Acomparisonofseismic‐hazardandriskdeaggregation.”

BulletinoftheSeismologicalSocietyofAmerica,96(6),pp.2021‐2039.

a).Finiteelementmodel b).Acapacitysurfaceofdesignedtimber‐basedbuilding

Page 26


ProjectCode:T1–3–C1 ProjectTitle: LocalizedRollingShearReinforcementofCLTSystemsSession#:2 Presenter:Tzu‐Hsien(Wallace)Shih


Woodisanorthotropicmaterial.Ithashighmechanicalpropertiesalongthelongitudinaldirectioncomparedtothoseintheothertwoorthogonaldirections.Oneoftheweakeststrengthpropertiesofwoodistherollingshearstrength.Itisthelateralshearstrengthonthelongitudinal‐radialplane.Intheoutofplanebendingapplicationsofavalueaddedcross‐laminatedtimber(CLT)product,rollingshearstrengthcangoverntheirdesigns.Asaresult,improvingtherollingshearcapacityofCLTwillbeakeytoenhancetheperformanceofCLT


Todevelopthefundamentalunderstandingontheimprovementoftherollingshearcapacity,CLTproductshouldbetestedexperimentally.InCLTfloorsystems,sinceconcentratedshearforcescanoccuraroundthecolumnsandsupports,highercompressivestressandrollingshearfailurealsohappenedaroundthesezones.Asareinforcementtechnique,woodendowelswillbeusedandembeddedonthecornersofCLTpanels,perpendicularlytolayers.Dowelsmayincreasetheresistanceofrollingshearstress.Size,numbersandconfigurationofthedowelswillbeconsidered.Testswillbedesignedtoresistuniaxialloadfirst.Furthermore,finiteelementmethodwillbeusedtosimulateandconductnumericalanalysisinordertocomparewiththeexperimentalresults.


Experimentdesignisunderprocessnow.TheexperimentisplannedtostartinJune.Duetothefirstyearofcoursestraining,resultsarelimited.


Woodendowelswillprovidemoreresistancetothefibersagainstrollingshearstress.Thecharacteristicofdowelswhicharemadealonggraindirectionmayalsoprovidereinforcementagainstperpendiculartograincompressionfailuretoresistcompressionforcesfromthecolumns.Finally,woodendowelsarelow‐costfasteners.Thatmeanswithlittleextracost,theefficiencyoftheuseoftimberstructureswillberaised.

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ProjectCode:T2‐1‐C4 ProjectTitle: ContinuityConnectionsforCLTPlatesinHybridSuperstructuresSession#:CB2 Presenter:MasoudSadeghi


CrossLaminatedTimber(CLT)panelsareverydesirablestructuralmaterialsandwithhighstrengthand stiffness, they have emerged as possible high‐rise structural area elements. Unfortunatelyhowever,goodasCLTmightbe,itcannotbeusedeffectivelywithoutaffordableandeffectivewaysoffasteningpieces together topossess thestrengthrequiredtosustain the loads involved.ThegoaloftheresearchistodevelopCLTplate‐to‐platejointingmethodsthatenablecreationofcontinuousslabsystems.SuchmethodsaretermedContinuityConnectionsthatcantransferthree‐dimensionalthrust,shearandmoment forcesassociatedwithULSandSLSperformancesofslabs. Although focus isonfloorslabsthatalsofunctionasdiaphragms,thejointingtechniquesenvisagedwouldalsobesuitablewithorwithoutmodificationforslabsingeneral(e.g.highperformanceshear‐walls).


ToevaluatetheinfluenceoftheconnectionsonthevibrationalserviceabilityperformanceoftheCLTflooring systems, a series of ambient vibration experiments have been carried out on the flooringsystemsmade from 2 CLT panels and then focuswas on the ability of the common types of joints(Half‐lappedandSingle‐splinejoints)tocarrytheloads.IntendistoimprovethebehaviourofthesejointsandconsequentlyCLTdiaphragmsfunctionasasubstituteforreinforcedconcretediaphragmsinhigh‐riseandhybridstructures.Theresearchmayleadtoaninnovativetypeofconnection.


Sofar,anumberofvibrationalandlateralsheartestshavebeencarriedout.Resultsofvibrationtestsshow that panel‐to‐panel joints greatly affect the response characteristics ofmulti‐panel CLT floorsystems.Resultsofedge‐to‐edgein‐planeshearconnectiontestsinCLTslabsshowedthathalf‐lappedconnectionsperformedbetterthansplineconfigurationsintermsofStrength,stiffnessandductility.Placing washers in under heads of self‐tapping screws can significantly increase the capacities ofeither half‐lapped or single‐spline shear joints in CLT slabs. It also should be noted that someinadequacies exist in contemporary European Yield Model type methods for calculating designcapacitiesofself‐tappingscrewjointsinCLT.


Results indicate thatwith somemethods it is possible to enhance the stiffness and strength of thementionedjoints.However,italsoneedstobeacknowledgesthatsuchconnectionshavebeenfoundto performpoorly in terms of out‐of‐plane behaviour of CLT slabs. This indicates need to considerfunctionality of connection methods from broad perspectives associated with performance ofsuperstructure systems, and not to simply focus on an isolated question like the in‐plane shearstrengthorstiffnessofconnections.

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ProjectCode:CB3 Project Title: Withdrawal Resistance and Embedment Strength ofFastenersinTimberandCLTPanels

Session#:2 Presenter:ShawnKennedy


CSAO86StandardforEngineeringDesigninWoodpresentsdifferentdesignequationsforwithdrawalresistanceofwoodscrewsandlagscrewsintimberconnections.Thedowelembedmentstrengthoffastenersinsawntimberandglued‐laminatedtimberiscalculatedusingrelativedensityofwoodandthe fastener diameter. No design equations are presented in the CSA O86 for calculation of thewithdrawal resistance and the embedment strength in cross‐laminated timber (CLT) products.Therefore,thepresentresearchprojectisfocussedonthreemainobjectives:

1. Develop a design equation forwithdrawal resistance for threaded fasteners in sawn timberandglued‐laminatedtimber;

2. Evaluatevariousmodelsofdowelembedmentequationsforsawntimberandglued‐laminatedtimberanddeterminetheiraccuracy,and;

3. Developequations fordowelembedmentstrengthandwithdrawalresistanceof fasteners inCLT.


Research project included approximately 3000 tests on various species of sawn timber, glued‐laminated timber and CLT produced in Canada. Fasteners under study were lag screws and self‐drillingscrews.WithdrawaltestswereperformedinaccordancewiththeEuropeanstandardEN1382andtheembedmenttestswererealisedaccordingtoASTMD5764half‐holetestmethod.


Thefollowingresultsandconclusionsarepresented.

1. The CSA O86 design equation for wood screws is chosen to determine the withdrawalresistanceofallthreadedfasteners.

2. Noneof theexistingdesignequationswere foundaccurate topredict thedowelembedmentstrength in sawn timber and glued‐laminated timber. Analysis of results indicated that thediameter greater than 6mm is not significantly related to the embedment strength. A newdesignequation,takingintoaccountthewoodrelativedensityonly,isproposed.

3. TheCSAO86woodscrewequationwasalsochosenforcalculationofwithdrawalresistanceofthreaded fasteners in CLT. Dowel embedment strength of fasteners in CLT can be obtainedwithtwoapproaches.FirstapproachispresentedintheUSeditionoftheCLTHandbook,whilethesecondapproachisappliedintheEuropeanstandard.


AllresultsarebeingproposedtotheCSAO86TechnicalCommitteeforpotentialadoptioninthenexteditionofthedesignstandard.

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ProjectCode:T2‐15‐C5 ProjectTitle:DevelopmentofInnovativeHybridTimber‐SteelMoment‐ResistingFrameforSeismic‐ResistantHeavyTimberStructures

Session#:2 Presenter:RyanGohlich


The goal of this project is to improve the seismic performance of heavy timber structures in highseismicareasbytakingadvantageofboththelightweightoftimberandthehighductilityofsteel.Thiswill be achieved through the development of an innovative hybrid timber‐steel moment‐resistingconnection that will act as a localizedmoment yielding hinge at the beam‐column interfaces. Sincewood is inherently brittle, it is not known for high seismic performance. With this connection, allseismicdamageandenergydissipationwillbeaccommodatedbythesteel,while the timbersectionswillbecapacitydesignedtoremainundamagedintheeventofanearthquake.Withtheimplementationofthisnewconnectionitwillbepossibletodesignmulti‐storeytimberstructureswithanachievableductilitycomparabletothatoftypicalsteelstructures.


A six‐storey prototype building located in Victoria, BC will be designed using response spectrumanalysis, assuming that all seismic energy will be dissipated by the steel moment connection. Aniterativeprocesswillbeundertakentochoosesectionsizesforthedesignofthewoodmembersandtoobtainanappropriateorderofmagnitudefortheloadsthattheproposedconnectionwillresist.

Innovativeconceptsforthedesignofthisreplaceablesteelmomentconnectionwillbedevelopedandevaluated with assistance from FPInnovation. This will involve the design of reliable high‐strengthconnections between the steel yielding link and the timber beam and column. Thiswill be themostchallenging aspectsof the research since the steel‐timber connections shoulddevelopnearly the fullmomentcapacityofthewoodmemberstobeefficient,andmustbedesignedtoavoiddamageintheseconnectionswhenthesteelyields.

Prototypesofafirststoreyconnectionwillbeconstructedandtestedinthelaboratorytoevaluatetheperformance of the system. Once the experimental behaviour of the timber‐steel connection is wellunderstood,a samplebuildingmodelwillbeconstructedusing thedevelopedhybridmoment frame.Thebehaviourofthisstructurewillbecomparedtothatofanequivalentsteelbuilding.


Existing research in the area of steel links and hybrid timber‐steel moment connections has beenreviewedandprototypebuildingdesignisunderwaytoobtainrealisticdesignloads.


Thekeyoutputof thisresearchwillbethedesignofan innovativehigh‐ductilitymomentconnectionthatwillimprovetheseismicperformanceofmid‐riseheavytimberstructures.Inaddition,thedynamicbehaviour of a structure using the proposed connection will be evaluated. The use of these newconnectionswillincreaseeaseofrepairandinitialerection,aswellasreducethecostofrehabilitationofthesestructuresafteraseismicevent.

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ProjectCode:T2–3–C4 ProjectTitle: DevelopmentofNovelConnectionSystemsforCLTInfilledSteelMomentResistingFrames

Session#: Presenter:JohannesSchneider


WoodframebuildingsareallowedtobebuiltuptosixstoriesaccordingtothepresentBCbuildingcode.Combiningsteelandwoodinastructuralbuildingsystempresentsaveryefficientconstructionconcept.Firstattemptstocombinethosematerialsinabuildingshowedgreatperformanceinseismicevents.Theadvantageofatimbersteelhybridstructurecanbefoundinacceleratederectiontimeaswellaslessbuildingweight,whichresultsinlighterstructuralelements.


Toconnectasteelmomentresistingframewithacrosslaminatedtimber(CLT)wallshowthebiggestchallenge.Inordertoprovideenoughstiffnesstothesystem,butatthesametimebehaveductileunderwindloadsandinearthquakes,theconnectingelementbetweensteelframeandinfillwallhasbeenidentifiedasakeyelement.Themainchallengeistofindaconnectingsystemwhichwillbeoptimizedfortheapplicationinawood‐steelhybridstructure.


Anumberofdifferentconnectorshavebeentestedwithdifferentloadingprotocols.Monotonicandcyclictestshavebeencompletedtoobtainamaximumrangeofdata.Byanalyzingthecommonlyavailablebrackettypeconnections(whichareappliedwithCLTbuildings)abigpotentialforimprovingtheconnectingmethodforahybridtimbersteelstructurewasdiscovered.Anewapproachwasfoundinatube‐typeconnection.Ahollowtubeincombinationwitharodboltedtothesteelframeperformedverywellundermonotonicaswellasundercyclicloadingprotocols.Thetubeconnectionprovidesanumberofadvantages.Itcanbeinstalledveryfast;stiffnesscanbeadjustedinasimplemanner,inspectionsoftheconnectionafterseismiceventscanbedonevisually,andincaseoffailureaneasyreplacementcanbedoneveryquicklyastheconnectionisdesignedthatonlythesteelpartfailsandtheCLTpaneldoesnotexperiencedamage.


Thetestresultsof30tubeconnectionsofvariousdiameterswillbeanalyzedandcomparedwiththebrackettypeconnection.TheconnectiontestdatawillbeusedtomodeltheconnectionbehaviourwhichwillbeincorporatedinaFiniteElementmodeltoperformaparametricstudyonvariousfactors,suchasdiameter,tubewallthickness,androddiameter.Thefinalgoalistobeabletounderstandandmodelthisconnectionandbeabletoapplythatfortimber‐steelhybridsystems.

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1st International Keynote Speaker: High‐rise timber buildings in Europe – projects, challenges, solutions and future development

Dr. Stefan Winter, Technical University of Munich

'Holz 8' (= timber 8) in Mietraching, Germany one of the highest timber buildings in Europe

Owner: B&O design: Schankulla Architects Munich.

Engineering: bauart construction company, Munich. Photo: Huber&Sohn, Bachmehring.

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Technische Universität München Lehrstuhl für Holzbau und Baukonstruktion Univ.-Prof. Dr.-Ing. Stefan Winter

High-rise timber buildings in Europe – projects, challenges, solutions and future

development

Abstract

To start with a short explanation: Europe (in the sense of EU) is a sample of 27 member states, based on the European contracts responsible by themselves for all safety regulations, and therefore also for building regulations. In addition some of the member states are made up of more or less independent countries/regions, responsible by themselves for building regulations (e.g. in Austria or Germany). That’s the reason why we face so much different building regulations in Europe. And it is the reason for difficult and long lasting changes in regulations. But since the 90’s and especially since 2000 thinking starts to change, regulations changed and an increasing number of ‘nearly’ or high-rise multi-storey timber projects were realised, most of them not above eight storeys. In parts of Europe a real ‘hype’ started for new residentials and office projects in timber structure, partly supported by refurbishment and densification of housing and urban areas, e.g. in Zurich, Switzerland, and Munich, Germany. Projects in several European capitals will be demonstrated in the presentation.

But as up to now especially the ‘nearly’ high-rise buildings with more than 5 storeys are ‘outside’ of building regulations in some of the member states, exceptions in the area of fire regulations are necessary. To enable approvals and to avoid non-controllable cavity fires, massive timber (CLT, Glulam) or massive-timber/concrete hybrid constructions were chosen in many cases. Timber frame structures are also used but normally only in the range up to five storeys. As staircases are built in concrete, special investigations and structures are necessary to limit the vertical deformation of the timber structure, another argument for CLT. New projects will use also massive-timber staircase and elevator shaft – a first eight storey pilot project is presented.Facades are made out of mineral-wool based ETICs (based on technical approvals), ventilated claddings of all kind of materials and in some cases timber claddings are applied.

Experience demonstrates that the structural and fire design is a minor problem, but moisture safety requires more alertness. First damages in multi-storey hybrid buildings lift the finger to allocate attention to driving rain safety and quality control instruments.

Fire safety of the structures are given by fire resistance up to REI 90, even fire separating walls are tested and implemented. Most of the structures are using gypsum based claddings to improve fire resistance. But many architects and owners want to see even partly wooden surfaces to use the positive influence of timber to indoor climate, as well as haptic and optic quality. That gives another reason to use massive timber structures, sometimes also as composite structures, examples will be shown in presentation. In terms of fire safety problems mainly occur, when integrating HVAC, water and electrical installations. Missing approvals of fire shutters for timber structures or insufficient planning coordination causes mistakes and damages.

Challenges are in future the development of building regulations (including the ‘dream’ of an European Building Regulation), improvement of economic solutions, e.g. by increasing standardisation of details and prefabrication/industrialisation, further education of planners and builders not used to timber and ---- moisture safety concepts to provide long-term robustness!

KEYWORDS: high timber buildings, construction, fire safety, moisture risc, building regulations, further development

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ProjectCode:T3‐1‐C7 ProjectTitle: FireRiskAnalysisSession#:3 Presenter:XiaoLiandPingRao


Performance‐based building fire safety design provides the possibility of awider use ofwood as abuildingmaterial.Butwoodisacombustiblematerial thusmoreattentionshouldbepaidtoensurethatthebuildingenvironmentissafe.AtCarletonUniversity,aquantitativefireriskanalysiscomputermodelCUrisk isbeingdeveloped toevaluate the fireperformanceofbuildings.Thisproject aims todevelopnewsubmodelor improveexistingsubmodelsso thatCUriskcanbeused toassess the firesafetyofmid‐risebuildingsunderdifferentconstructiontypes.


AseriesoffullyscaleexperimentaltestshavebeenconductedatCarletonUniversity.ThetestdataareusedtoimproveCUrisksubmodels.ThenCUriskisusedtocomparedifferencesamongbuildingsmadeofnoncombustibleandcombustiblematerials.Eventtreemethodisappliedtoconstructfirescenariostructuresforeachdesign.


Basedonthefiretestresults,thecontributionoftimberstructuretotheroomfiredevelopmenthasbeen implemented into CUrisk. Amodule is added to the SmokeMovement submodel to take intoaccount the effect of combustible structure on the fire development. The fuel contribution of thetimberstructuretothefireisbasedonthecharringratesandcharringareaofthetimbermembers.NowCUriskisusedtoshowthecontributionofcombustiblestructureinvariousconstructiontypes,includingnoncombustible,light‐frametimber,protectedCLTandunprotectedCLTbuildings.CUriskisusedtoevaluatetheimpactsofbuildingareaandbuildingheightsonthefirerisks.Simulationresultsdemonstratethat increasingthebuildingheightto12‐storeydoesnot increaserisksandthereisnoincreaseinrisktolifeinalarge‐size6‐storeybuilding.


TheCUriskmodelhastheabilitytoperformriskanalysisofvariousconstructiontypes,aswellastheimpactofbuildingsizeorbuildingareasonthefirerisk.ThestudydemonstratesthatCUriskcanbeused as an important tool to seek fire risk information of a proposed building, thus it can helpengineerstoevaluatebuildingfireperformanceanddesignbettersolutions.

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ProjectCode: ProjectTitle: FireBehaviourofCrossLaminatedTimberPanelsSession#:3 Presenter:AlejandroR.Medina


Astheworld’sdesireforrenewableresourcescontinuestogrow,sodoestheresearcharoundthe globe involving wood products. The use of wood in building construction is greatly restrictedbecause of the material’s presumable low fire performance. The National Building Code of Canada(NBCC)currentlylimitsthenumberofstoreysandfloorareaofcombustiblebuildingconstruction.Myresearchstudyexamined3fullscaleroomfiresandmodifiedanumericalcomputermodeltodeterminethefireresistanceofCrossLaminatedTimberpanels.


During this studywe conducted3 full scalepartiallyprotectedCrossLaminateTimber (CLT)roomfiretests.Recenttestsbycolleagueshaveshownthatfullyprotectingtheinteriorroomsurfaceswithgypsumboardresultsincompletecontentburnoutwithoutwallorceilingfireinvolvement.OntheotherhandfullyunprotectedtestsproducedintensefireswithhighinvolvementofCLTwallandceilingpanels.

OurtestswereperformedonpartiallyprotectedCLTroomsinordertodeterminethemaximumpercentageofunprotectedsurfaceareathatwillresultinself‐extinguishmentaftertheroomcontentshavebeenconsumed.TemperatureofroomandpanelcrosssectionsaswellasHeatReleaseRate(HRR)wascollected.Thisdatawillbeusedtodeterminethepanels’charringrate,charringdepth,andoverallbehaviourofthefire.

A numerical 1‐dimensional heat transfer model has been created to determine the fireresistanceofCLT loadedwalland floorpanels.Thenumericalmodel takes intoconsiderationpanel’sheight,layerthickness,species,loadingcondition,firetypeandwhetherornotthepanelsareprotectedwithgypsumboards.ThistoolwillprovideengineersandscientistsaquickmethodtoevaluatethefireresistanceofCLTfloorsandwallstoaidtheminthedesignprocess.


Eachofthethreetestsdifferedinthepercentageofunprotectedareaaswellasthenumberofwallsprotected.TheresultsshowthatCLTpanelscanbeusedsafelyinacompartmentaslongastheunprotectedinteriorsurfaceislimited.


Ultimately,throughtheuseoftheoreticalaswellasexperimentaldata,thisstudywillprovideabetterunderstandingofCLTpanels’fireresistanceandaidonthefireresistancedesignofCrossLaminatedTimberpanels.

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ProjectCode:T3–4–C5 ProjectTitle: FirePerformanceofTimberConnectionsSession#:3 Presenter:Aaron AkotuahOhene


Connections are critical areas in a building structure. They have to be designed to transfer loadsefficientlybetweenstructuralelements.Traditionaltimberconstructiontypicallyentailsconnectionsbetweentimberandsteelbuildingelementsandsuchaconnectionbehaviour innon‐fireconditionsareaddressedwellinstructuralbuildingcodes.Theperformanceofhybridsteel‐timberconnectionsin fire is evenmorecomplex sinceboth steel andwoodmaterialsbehavedifferently in response toelevated temperatures. Three types of connections; Concealed Shear tab, Exposed and Seatedconnectionsareinvestigatedinthisresearchwiththefollowingobjectives:

1.Todevelopafiniteelementmodelforsimulatingthefire‐resistancetestsofconnections

2.Todeterminetherelativefireresistanceofthedifferentconnectiontypes

3.Toexaminetheinfluenceofloadratioonthefireresistanceofallconnections


Experimentalworkofseveralfireresistancetestshadbeenalreadyconductedontheconnections.Afinite element model was then developed in this research to simulate the fire resistance tests.ABAQUS, a commercial finite elementprogramwas employed todo this. The fire andheat transferweremodelled appropriately as obtained from the test fire scenario (subjecting test assembly to astandard design fire)while the structural behaviourwasmodelled using appropriate stiffness andstrengthpropertiesoftheconnectionassembly.Thenumericalsimulationwasdoneasasequentiallycoupled thermal‐stress procedure where an applied load was maintained on the assembly andsubsequentlysubjectingittograduallyincreasingtemperaturesuntilultimatefailurewasreached.


Connection Plate Bolt Diameter

(mm) Load ratio

(%)

Failure Time (mins)

Variation (%)

Test Model

Concealed 19.1 30 35 34.7 -0.86

100 15 13 -13.3

Exposed 19.1 60 25 27.7 +10.8

100 18 14.6 -18.9

Seated 12.7 60 34.5 35.5 +2.9

100 15 16.5 +10.0


Therelativeperformanceofconnectionconfigurationsinfireconditionsdetermineshowconservativetheyare indesign for fire resistance.This canprovide simpleguidelines forbuildingdesignersandconstructors. Also,differentbolt sizes,numbers and configurations canbeperformedas a furtherparametric analysis in future models which can give rise to new recommendations for the fireresistanceofsuchconnections. Page 36


ProjectCode:T3‐7‐C2 ProjectTitle: InnovativeWaystoMakeCLTPanelsSoundAbsorptiveSession#:4 Presenter:BandaLogawa

Background and objectives

With the growing interest in applications of cross‐laminated timber (CLT) as building materials, their

acoustical properties have been the focus of much current research. While most of them are centered on

sound‐transmission characteristics of CLT panels, there have been very few dedicated to analyze their

sound‐absorption characteristics and how to optimize them. This project is aimed to investigate ways to

improve the sound‐ absorption characteristics of the panels by integrating array of Helmholtz‐resonator

(HR) absorbers into the panels and establish design guidelines for CLT‐HR absorber panels for various

room‐acoustical applications.

Research method/approach

Existing theoretical models of HR absorbers with various neck shapes and dimensions are reviewed coded.

Based on these models, prototype HR‐ CLT panels which satisfy sound performance targets and design

criteria for various room‐acoustical applications will be manufactured and tested. The performance of

these prototypes will then be compared to typical CLT panels currently installed in multiple buildings in BC

as well as other commercial acoustic products. Three different measurement methods are considered to

evaluate the sound absorption performance: impedance‐tube, spherical decoupling, and reverberation‐

room methods.

Summary of results to‐date

Several efforts have been done to measure and analyze sound absorption characteristics of exposed CLT

surfaces in multiple buildings in British Columbia, investigate suitable methods and locations to measure

both normal and random incidence sound absorption characteristics, studied the current manufacturing

method of CLT panels, and create acoustic models of CLT‐HR absorber panels with various shapes and

dimensions. Based on these results, prototype panels will be manufactured and tested in order to validate

the theoretical models.

Expected key output and potential impact of research

Theoretical and experimental models, showing the relation between the dimensions of the HR absorbers,

resulting absorption coefficient of the panels, and other relevant aspects of the panels (structural

performance and airborne and flanking sound transmission) will be produced by the end of this project.

Based on these models, design guidelines for CLT‐ HR absorber panels for various room‐acoustical

applications will be established for future commercial consideration.

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ProjectCode:T1‐4‐C1 ProjectTitle: DevelopmentofNon‐destructive(NDT)TechniqueforCLTGrading&QualityControl

Session#:4 Presenter: JianhuiZhou


CLTpanelsaretypicallyusedasload‐carryingplateelementsinstructuralsystemssuchaswalls,floorsandroofs.Keycriticalcharacteristicssuchasin‐planeandout‐of‐planebendingstrength,shearstrengthandstiffnessmustbetakenintoaccountindesignsincetheyaffectnotjustsafetybutalsoserviceabilityperformancesuchasdeflectionandvibration.Therefore,accuratemeasurementofitselasticpropertiesisofgreatimportanceforpredictingthemechanicalbehaviorduringstructuraldesign.AswellonlinegradingofCLTpanelswillensurethateachpanelproducedmeetsthetargetdesignproperties.However,thestaticmethodsandcurrentNDTmethodshavesomelimitations.

Theobjectivesare, Toevaluatetheinfluenceofsupportconditiononthemeasurednaturalfrequencies,and

proposeasupportingsystemfortestingCLTpanel; Tocomparetheelasticpropertiesmeasuredusingtheproposedvibrationtesttechniqueand

thosemeasuredusingconventionalstaticmethods; Todevelopanalgorithmthatallowsidentificationofthethreecorrectnaturalfrequencies

frommeasuredspectrumsignals.


Theoreticalstudyonforwardproblemandinverseproblemofselectedboundarycondition Developmentofelasticconstantextractionalgorithmbyproposedvibration‐basedmethod

andstaticverification Identifythesensitivefrequenciesfromuptothreefrequencyspectra


TheproposedelasticconstantsdeterminationmethodbymodaltestingunderSFSFiseffectivetomeasuretheelasticconstantsofCLTpanels.TheuseoftheSFSFboundaryconditionrenderstheprocessofidentifyingsensitivenaturalfrequencysimple.Withtheinitialpredictionofnaturalfrequencywithmodeorderandtheimaginarypartpatternofthefrequencyresponsefunction,thesensitivenaturalfrequenciescanbeefficientlyidentifiedfromthefrequencyresponsefunctions.TheExandEyvaluesdeterminedbytheproposedmethodagreewellwiththecorrespondingstaticvalues.Howeveritwasfoundthattheeffectsofsupportconditionsontheaccuracyofmeasuredelasticconstantsrequiresmoreinvestigation.TheGxyvaluemeasuredbytheproposedmethodisreasonablecomparedwithpublishedvalues,andwillneedtobecomparedwithvaluesmeasuredbystatictestmethodinfuturestudy.


TheproposedmethodbedevelopedintoafastandreliableNDTmethodforCLTelasticconstantsmeasurementsandqualitycontrol.

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ProjectCode:T3–5–C2 ProjectTitle: VibrationalperformanceofCLTfloorSession#:4 Presenter:SaulHernandez


Cross laminated timber (CLT) is a multilayer engineered wood product that can be produced in a wide range of thicknesses and lengths. European experience has shown that replacing heavy concrete floors with CLT slab is an efficient and cost effective application of CLT. When used in floor construction, proper design consideration must be applied in order to ensure satisfactory serviceability performance under human footstep impact.

The objective is to examine the influence of end support conditions and panel‐to‐panel joint on the natural frequency, static deflection and damping ratio of CLT floor systems. Ultimately the goal is to producerecommendationsoncalculationofnaturalfrequenciesofCLTfloorswithvarioussupportcharacteristics.


To achieve the above objective, it is necessary to perform testing of CLT floors both in the laboratory, where support conditions can be carefully controlled and characterized, and in situ, to study the influence of ‘real life’ construction details.

The methodology is presented in two phases. The first phase consists of laboratory tests on a single‐span system. The second phase will consider a larger CLT floor structure in a double‐span configuration. End support conditions to be evaluated include support stiffness caused by various practical end support conditions such as load from wall, direct fastening using screws and ledger. The present activities concentrate on laboratory experiments to measure the effect of rotational stiffness and span on the natural frequency, damping, and static deflection of one‐way CLT panels. In addition, vibration tests will also take place on CLT floors in CLT buildings under construction. The results of these two phases of experimentation offer an understanding of how support conditions affect the natural frequency and damping of a CLT floor. Throughout the project, the impact modal testing approach will be used to measure the natural frequencies and damping of test floors.


Laboratory vibration tests of floor simply supported on two sides (SFSF) and four sides (SSSS): ‐ Natural frequencies identified. Leissa (1993) model gives accurate prediction of the first natural frequency of CLT floors supported on two sides (SFSF). For floors with four sides supported and small aspect ratio (span to width), the SSSS model could provide reasonable predictions.

In‐situ tests of two 12 meter double‐span CLT floors in a 3 storey CLT building: ‐ The first natural frequency was identified and predicted accurately using Leissa model (assuming single span of 6 meters). Further evidence is necessary to validate double‐span prediction models.

Preliminary results are promising employing vibration method proposed by Sobue and Katoh (1982) to measure Ex, Ey and Gxy of CLT panels.

Laboratory end support condition tests on a 3‐layer CLT panel supported on two sides; applying load on supported edge, direct fastening using wood screws, and with a ledger support. ‐ Applying load on supported edge and the use of screws cause an important increase on the natural frequency of the 3‐layer CLT panel supported on two opposite sides. Deflection, under a 1kN load at center, decreases as the load and the number of wood screws increases. Ledger support has minimal effect on natural frequency and deflection. Damping ratio remains fairly consistent.

Laboratory span tests; ‐ A decrease in span causes an increase in natural frequency and a decrease in deflection under a 1kN center load. Damping ratio remains consistent.


This study will contribute to a fundamental understanding of the influence of support characteristics on natural frequencies of CLT, such as support stiffness and double‐span system, and help explain the discrepancies between predicted natural frequencies using various calculation methods and test values.

Ultimately, it is expected that recommendations for calculation of natural frequencies and damping capacity of CLT floor systems for design use will be generated.

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2nd International Keynote Speaker: Building Envelope Performance of Wood‐Based Building Systems: Research Perspective from the US

Dr. Samuel Glass U.S. Forest Products Laboratory, Madison, WI, USA

Chamber for Analytic Research on Wall Assemblies

exposed to Simulated weather (CARWASh) facility

US Forest Products Laboratory

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Building Envelope Performance of Wood-based Building Systems: Research Perspectives from the US

Sam Glass, US Forest Products Laboratory

Network for Engineered Wood-based Building Systems (NEWBuildS) Workshop 2014

Abstract

Building envelope design has key implications for the energy performance and durability of structures as well as for indoor air quality and occupant comfort. Wood-based structural systems offer a number of advantages for designing and constructing buildings that are energy efficient, environmentally responsible, attractive, comfortable, durable, and safe. One of the perceived disadvantages of wood-based construction, however, is vulnerability to moisture-induced damage. This presentation focuses on research aimed at improving building envelope moisture performance and durability.

In recent years energy efficiency requirements for buildings have undergone considerable changes in the United States. Trends related to building envelope requirements in the US will be highlighted. The presentation will discuss building envelope research needs from the perspectives of the US Forest Products Laboratory, the US Department of Energy’s Building America program, and the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).

Several research projects on building envelope performance at the US Forest Products Laboratory will be highlighted. These include field studies of wood-frame test buildings near Seattle, Washington, in conjunction with APA–The Engineered Wood Association and Washington State University, and near Washington, DC, in conjunction with Home Innovation Research Labs. Also included is a project on moisture performance of cross-laminated timber wall assemblies.

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ProjectCode:T4‐2‐C10 Project Title : Characterizing Wind‐driven Rain Loadand theEffectiveness of Overhang on Reducing Wind‐driven Rain Wetting forMid‐riseBuildings

Session#:5 Presenter:UzzwalKumarDebNath &VincentChiu

BackgroundandobjectivesDrivingrainisoneofthemostimportantmoisturesourceaffectingbuildingfacades.Inordertoensurelong‐termdurabilityofhighlyenergyefficientandsustainablebuildings,itisimportanttoadvanceourknowledgeonthewind‐drivenrainloadanditsimpactonthebuildingenvelopeperformance.However,sofarthereisverylimiteddataontheamountofwind‐drivenrain.Theobjectivesofthisprojectare:

• ToquantifyWDRloadsondifferenttypesofbuildingsindifferentclimaticregions.• TodeterminetheeffectivenessofoverhangonthebuildingfacadeagainstWDR.• TodevelopamethodologytoquantifyWDRloadformid‐risebuildings.


• FieldmeasurementsofWDRonmid‐risebuildingsindifferentregions.• FieldmeasurementsofWDRonasix‐storybuildingfittedwithadjustableoverhangin

Vancouver.• AnalysisofHistoricalData(i.e.,WindDirection,WindSpeed,Rainfall)tocharacterizewindand

rainconditionsfordifferentclimaticregions.• Catchratiosandwallfactorsanalysesbasedonmeasureddatatoimprovetheexistingsemi‐

empiricalmodels.• CFDmodelingtogenerateaWDRdatabasetoprovidegeneraldesignguidelines.


• Forallthreeregions(i.e.,Montreal,Fredericton&Vancouver),80%ofthetimetherainfallintensityislessthan2mm/hr.ForMontreal&Frederictonlessthan5%ofthetimeandforVancouverlessthan3%ofthetimetherainfallintensityexceeds4mm/hr.

• Forallthreeregions(i.e.,Montreal,Fredericton&Vancouver),thewindspeedtypicallyvariesintherangeof2m/sto8m/sandlessthan10%ofthetimewindspeedexceeds8m/s.Windspeedishigherduringrainhoursascomparedtoallhours.TheprevailingwinddirectioninMontreal,FrederictonandVancouveriswest,northandeastrespectively.

• Theamountofraindepositedonthebuildingsurfacevarieswithlocations.Thecornerandedgesreceivedthehighestamountofrain.

• Thecatchratiovarieswithrainevents,namelyrainfallintensity,windspeedandwinddirection;catchratiosincreasewiththeincreaseofwindspeedandhighercatchratioswhenapproachingwindisnormaltothefacade.

• ThewallindexcalculatedbytheISOstandardoverestimatesdrivingrainamount.Expectedkeyoutputandpotentialimpactofresearch

• ThisstudywillgenerateauniquesetofmeasurementstoquantifytheeffectivenessofoverhangandbettercharacterizetheWDRdistributiononmid‐risebuildingsfordifferentCanadianclimaticregions.

• Thisstudywillresultinanimprovedsemi‐empiricalmodeltoquantifyWDRloadonmid‐risebuildings.

• AvalidatedCFDmodeltogenerateaWDRdatabasewithdifferentbuildinggeometryandoverhangconfigurationstoprovideabetterquantificationofWDRloadonbuildingenvelopes.

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ProjectCode:T4‐5‐C10 ProjectTitle: Field test of hygrothermal performance of highly insulated wall assemblies

Session#: Presenter:SabrinaD’Ambra,LinWang,HuaGe

Backgroundandobjectives:

Cross‐laminated timber (CLT) panels have potential market in North America for building mid‐rise or even taller structures due to their good structural and fire safety performance, light weight, and prefabricated nature. To ensure long‐term durability when used in building enclosures, the hygrothermal performance of CLT wall assemblies needs to be evaluated in terms of wetting and drying potential. In the first phase of this project, a test wall consisting of sixteen 0.6 m by 0.6 m CLT panels made of five different wood species (or species groups) and four different wall assemblies was constructed. The CLT panels were initially wetted with the moisture content (MC) in the surface layers approaching or exceeding 30%, and monitored for MCs and temperatures at different depths over one year in a building envelope test facility located in Waterloo, Ontario. The drying behaviour of these panels was analysed and the measured MCs over time were compared to simulation results using a commercial hygrothermal program. The simulation results generally agree well with the field data at MCs below 26%. However, it was found that the hygrothermal simulation program tended to overestimate the MC in the centre of the panels by up to 5 to10%, and simulated MCs at locations deep into the CLT panels were not as responsive to changes in ambient conditions, as the measurements indicated for assemblies with high exterior permeance. To be able to assess the long‐term hygrothermal performances of CLT constructions of various configurations in different climates, the hygrothermal model needs to be further improved. The objectives of the second‐phase of this project are: ‐ Further refine the WUFI model and investigate the discrepancy between simulations and

measurements ‐ Sensitivity analysis of material properties, moisture loads, and climatic conditions ‐ Recommendations on the application of CLT construction in different climatic conditions and its use

in combination with different materials

Research method/approach:

‐ Hygrothermal simulations using WUFI Pro

‐ Sensitivity analysis: variation of material properties, variation of moisture loads, and climatic

conditions

‐ Comparison between simulations and measurements

Summaryofresultsto‐date:

‐ Sensitivity analysis showed that the sorption isotherm has the most significant influence on the simulation results among the hygric properties investigated i.e. vapour permeability, sorption isotherm, liquid transport coefficients

‐ The effect of solar radiation as a sensitivity variable was not significant for the assemblies tested


‐ Procedure using WUFI Pro to model the hygrothermal performance of CLT wall assemblies

‐ Recommendations on durable CLT construction under different climatic conditions

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Project Code : T4-7-C10 Project Title : Developing Durable Wood-frame Building Envelope Systems for Net-zero Energy Ready Buildings

Session #5 – (D&E 3) Presenter : Michael Fox

Background and objectives:

Addressing climate change requires greater energy efficiency in building codes, which means that future building envelopes will be increasingly air tight and containing higher levels of insulation. These changes may have unintended effects on the long-term durability of wood-based components if the drying potential of the assembly is reduced. Wetting can occur as a result of interstitial condensation via air leakage and high relative humidity or as a result of rain leakage.

Research method/approach:

To investigate the risks associated with reduced drying capacity, six high R value wall assemblies were installed at a field test facility under controlled indoor conditions and natural exposure to exterior environment. Three of the six wall assemblies were designed to study the hygrothermal performance of 38 x 140 mm framed walls fitted with three types of exterior insulation (polyisocyanurate, XPS and Roxul mineral wool). The remaining walls were designed to investigate deep cavities filled with dense-pack cellulose or closed cell spray foam insulation (ccSPF). The conventional 38 x 140 mm framed wall served as a performance reference.

The test panels were instrumented with temperature, relative humidity, moisture content and heat flux sensors to investigate the hygrothermal performance of each wall through its 600 mm on-centre cavity space. Indoor air was injected at a constant flow rate to the insulation cavity to simulate air leakage during the winter of 2013. The air injection test was followed by an exterior water leakage test to simulate rain infiltration during the summer of 2013. These data were used to assess the condensation risks and drying potential of each wall assembly.

Summary of results to-date:

The background moisture content (MC) data indicated that most walls had a uniform distribution of moisture with the exception of the cellulose insulated walls. The moisture distribution within these walls was complicated by the stratification of moisture within the wall cavity with higher sheathing and plate moisture contents in the upper portions of the walls – the stratification was more exaggerated in the north facing walls.

The air injection test illustrated that the warmer OSB sheathing of the exterior insulated walls was less susceptible to wetting, which resulted in fewer interstitial condensation hours than the deep-cavity or datum wall types. Conversely, the lower framing-plates were most at-risk of moisture damage in the deep-cavity cellulose insulated walls due in part to the prolonged drying times.

The south facing I-Joist (S2) wall showed some promise for the deep cavity cellulose approach as its OSB sheathing moisture performance was lower than that of the south datum wall. Model analysis suggested that the lower OSB MC-values within this wall arose from lower initial moisture content of the cellulose insulation. These results suggest that the initial moisture content of the cellulose was highly variable within and between each of the I Joist and Double Stud test walls.

Expected key output and potential impact of research

To generate knowledge of the hygrothermal performance of energy-efficient wood-frame envelope systems, help the construction industry meet the increasing requirements for building energy efficiency, improve design and construction quality, and to improve confidence in the construction industry in using innovative building envelope assemblies and materials.

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ProjectCode: ProjectTitle: EnergyEfficiencyofMid‐riseBuildingSession#:Session5:Durability&Energy

Presenter:TanziaSharmin


Buildings are major consumers of energy throughout the world, exceeding both the heavy industrial manufacturing and transportation sectors in energy consumption. Optimizing energy consumption at the operational phase of a building’s life cycle can reduce its impact on the environment. According to the International Energy Agency (IEA), building sector is one of the most cost-effective sectors for reducing energy consumption. In cold-climate regions, heating load consumes a significant portion of total building energy, such that, by designing and constructing energy-efficient wall systems, this consumption can be reduced.

The goal of this research is to evaluate innovative energy-efficient wall systems which can potentially accommodate requirements for both hygrothermal and thermal resistance while providing required structural capability for mid-rise wood frame construction.


In order to ascertain the impact on building components of a whole range of real-time conditions buildings are exposed to, field measurements are necessary. For this purpose, a full-scale testing house is constructed using selected innovative wall systems in order to evaluate the long-term hygrothermal and thermal resistance performance of the selected exterior wall systems exposed to natural outdoor weather and controlled indoor conditions. Regarding the structural performance, laboratory testing on wall load-bearing capacity is conducted.


The R-values calculated from the collected field measurement data show that all the tested wall systems achieve the minimum assembly R-value (RSI) for wood frame construction of R-15.6 (RSI 3.45), as recommended by ASHRAE-90.1 (2007).


Ultimately, this research is expected to help identify which wall system performs with the optimal balance between thermal and structural criteria for energy-efficient mid-rise wood-frame construction.

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