UW Pavement and Buried UW Pavement and Buried Infrastructure ResearchInfrastructure Research

Dr. Mark KnightDr. Mark KnightUniversity of WaterlooUniversity of Waterloo

ExpertiseExpertise

Field and laboratory testingField and laboratory testingTrenchless pipeline:Trenchless pipeline:

construction, construction, condition assessment, condition assessment, renewal and renewal and asset managementasset management

Old roads, old pipes ?Old roads, old pipes ?

•• Superb constructionSuperb construction•• Little maintenance Little maintenance •• Low operational costsLow operational costs

•• When to rehabilitate?When to rehabilitate?

JACK

New roads over old pipes?New roads over old pipes?

We are not alone!We are not alone!

Jack appears in different figures!Jack appears in different figures!

………………but mostly not at the same time!but mostly not at the same time!

Field TestingField TestingOn going ResearchOn going ResearchAdedamola Adedapo PhD candidateAdedamola Adedapo PhD candidate

Alireza Bayat PhD candidateAlireza Bayat PhD candidate

HDD HDD vsvs Cut & CoverCut & CoverHDPE Pipe InstallationsHDPE Pipe Installations

Research Objectives:Research Objectives:Quantify pavement performance & Quantify pavement performance & deteriorationdeterioration

Quantify HDPE pipe behavior and Quantify HDPE pipe behavior and performanceperformance

During constructionDuring construction

Post constructionPost construction

Cut & Cover InstallationCut & Cover InstallationEquipment andEquipment and

Data Logging TrailerData Logging Trailer

HL3HL3--22 SuperpaveSuperpave SMASMA PMAPMA HL3HL3--11

East LaneEast Lane

West LaneWest Lane

0 m

0 m

153

153

283

283

420

420

567

567

709

m70

9 m

425

425 36

336

335

835

8

284

284 22

022

0

155

155

106.

410

6.4

122.

812

2.8

Weight in Motion ScaleWeight in Motion Scale

GeogridGeogrid

Oct 2003 Open Trench Install. of 200 mm HDPE PipeOct 2003 Open Trench Install. of 200 mm HDPE Pipe

April 2003 HDD Install. of 200 mm HDPE PipeApril 2003 HDD Install. of 200 mm HDPE Pipe

HDD INSTALLATIONHDD INSTALLATIONApril 2003April 20035.5 feet below ground surface5.5 feet below ground surface8 inch DIPS HDPE DR 178 inch DIPS HDPE DR 17Length = 75 feetLength = 75 feetPipe installation ~ 5 minutes Pipe installation ~ 5 minutes

Pipe Ring DeflectionsPipe Ring Deflections

Measure pipe Measure pipe change in shapechange in shape

Accuracy = 0.01mmAccuracy = 0.01mm

Data MonitoringData Monitoring

Pre and post pavement surveysPre and post pavement surveys•• 1.5 by 1.5 feet pavement grid1.5 by 1.5 feet pavement grid•• IRI surveysIRI surveys•• GPR surveysGPR surveys

•• Use best practices for restorationUse best practices for restoration•• Depth and length similar to HDDDepth and length similar to HDD

Cut & Cover InstallationCut & Cover Installation

A1 A1 A1A1

S2 S2

S3 S3

S2

P3

P2TDR 2

A1

TDR 3

T1

T3

T2

300mm

350mm

750mm

1.5 2.32.32.01.0 4.0

CO WL

Road CenterlineEast Pavement Edge

200mm HDPE PIPE

West Pavement Edge

~13.1m

P1

EL

A1 A1 A1A1

S2 S2

S3 S3

S2

P3

P2TDR 2

A1

TDR 3

T1

T3

T2

300mm

350mm

750mm

1.5 2.32.32.01.0 4.0

CO WL

Road CenterlineEast Pavement Edge

200mm HDPE PIPE

West Pavement Edge

~13.1m

P1

EL

A1 A1 A1A1

S2 S2

S3 S3

S2

P3

P2TDR 2

A1

TDR 3

T1

T3

T2

300mm

350mm

750mm

1.5 2.32.32.01.0 4.0

CO WL

Road CenterlineEast Pavement Edge

200mm HDPE PIPE

West Pavement Edge

~13.1m

P1

EL

Earth Pressure CellsAsphalt Strain GaugesSoil Strain GaugeWater Content Reflectometer

Temperature Probe

Soil & Pavement SensorsSoil & Pavement Sensors

MonitoringMonitoring

Construction and post construction:Construction and post construction:•• Pavement deteriorationPavement deterioration•• Pipe and soil responsePipe and soil response

Data LoggersData LoggersThree data loggersThree data loggers-- 20 sensors in soil backfill20 sensors in soil backfill-- 19 sensors inside HDPE pipe19 sensors inside HDPE pipeSensor readings: Sensor readings:

During installation = 10 secondsDuring installation = 10 secondsPost construction = 1 minutePost construction = 1 minute

Trigger sensitive to get loadingsTrigger sensitive to get loadingsData logger Internet accessible and Data logger Internet accessible and

controllablecontrollable

Elapsed Time (days)

Pipe

Def

lect

ion

(mm

)

200 300 400 500 600 700 800 900 1000

-0.2

0

0.2

0.4

0.6

0.8

TS1-D0TS1-D45TS1-D90

Pipe Deflections Pipe Deflections wrtwrt TimeTime

FLAC3D 3.00

Itasca Consulting Group, Inc.Minneapolis, MN USA

Step 15595 Model Perspective17:17:34 Wed Oct 04 2006

Center: X: 0.000e+000 Y: 2.000e+000 Z: -2.197e+000

Rotation: X: 0.000 Y: 0.000 Z: 340.000

Dist: 3.518e+001 Mag.: 1Ang.: 22.500

Axes Linestyle

XY

Z

Block Contour of SZZ Stress-1.1683e+005 to -1.1000e+005-1.1000e+005 to -1.0000e+005-1.0000e+005 to -9.0000e+004-9.0000e+004 to -8.0000e+004-8.0000e+004 to -7.0000e+004-7.0000e+004 to -6.0000e+004-6.0000e+004 to -5.0000e+004-5.0000e+004 to -4.0000e+004-4.0000e+004 to -3.0000e+004-3.0000e+004 to -2.0000e+004-2.0000e+004 to -1.0000e+004-1.0000e+004 to -6.5412e+002

Interval = 1.0e+004

Numerical Simulation ValidationNumerical Simulation Validation

Job Title: Geometry of OpenCut InstallationView Title: Area affected by Excavation

Trench Influence areaTrench Influence area

Job Title: Geometry of OpenCut InstallationView Title: Shear Plane

Shear ZonesShear Zones

2020

Investigation into MechanisticInvestigation into Mechanistic--Empirical Design MethodsEmpirical Design Methods

Alireza BayatAlireza Bayat

2121

Research ObjectivesResearch Objectives

Use CPATT field data to determining the Use CPATT field data to determining the pavement response (stresses and pavement response (stresses and strains) due to traffic and environmental strains) due to traffic and environmental loadingloading

Relating these responses to the Relating these responses to the pavement lifepavement life

Field Test ProgramField Test Program

Traffic Loading Traffic Loading 20042004--20052005

Typical Field Data Typical Field Data

500

600

700

800

900

1000

1100

1200

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5Time(sec)

Long

itudi

nal S

trai

n- A

SG5

(µm

/m)

Steering axleDrive axle

Trailer axle

Compression

Tension

-10

20

50

80

110

140

170

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5Time(sec)

Vert

ical

Str

ess-

TPC

1 (k

Pa) Steering axle

Drive axle

Trailer axle

Pavement Stress Pavement Stress

0

100

200

300

400

500

0 200 400 600 800 1000 1200 1400

Time (millisec.)

Pave

men

t Str

ess

(kPa

)

P1-20cm P2-60cm P3-95cm

First Axle Second Axle

Third Axle

Pressure Cell Data Pressure Cell Data vsvs PredictionsPredictions

0

100

200

300

400

0 20 40 60 80 100

Depth(cm)

Ver

tical

Str

ess

(kPa

)

Field MeasurementBurmister Method

0

20

40

60

80

100

0 20 40 60 80 100 120 140

Depth( cm)

Vert

ical

Str

ess

(psi

)

Circular method-case 1Point LoadMeasured

Repeatability and SurvivabilityRepeatability and Survivability

1st Axle (kPa) 2nd Axle (kPa ) 3rd Axle (kPa) Average 24.4 78.5 55.5 St. Dev. 1.86 4.83 5.31 Range 6.21 15.2 16.6

Only one of the asphalt strain gaugesOnly one of the asphalt strain gauges

Temperature ImpactsTemperature Impacts

-800

-600

-400

-200

0

200

400

600

800

1000

6/12 12 PM 6/13 12 PM 6/14 12 PM 6/15 12 PM 6/16 12 PMTime(sec)

Long

itudi

nal S

trai

n be

low

the

Asp

halt

Laye

r

0

5

10

15

20

25

30

Tem

pera

ture

bel

ow th

e A

spha

lt La

yer

ASG1 ASG2 ASG3 ASG5 Temperature

(µm

/m)

(°C

)

Temperature

Asphalt Strain Gauges

0

20

40

60

80

100

120

140

160

180

15 20 25 30 35 40Average Asphalt Temperature

Vert

ical

Str

ess-

TPC

1 (k

Pa)

(°c)

Some FindingsSome Findings

Response models based on elastic multilayered Response models based on elastic multilayered theory produced stress values lower than the theory produced stress values lower than the measured stressmeasured stress

Repeatable data with a low standard deviationRepeatable data with a low standard deviation

Instrumentation survivability rate of 95%Instrumentation survivability rate of 95%

Impact of environmental factors such as Impact of environmental factors such as temperature, frost, and moisture on gauge temperature, frost, and moisture on gauge performanceperformance

Signs of an Aging Signs of an Aging Sewer SystemSewer System

City of Winnipeg, ManitobaCity of Winnipeg, ManitobaLosing 1.9 trucks/cars per yearLosing 1.9 trucks/cars per year

What a pothole! What a pothole! KITCHENER, ONKITCHENER, ON(Mar 15, 2005)(Mar 15, 2005)

Sinkhole from watermain break causes havoc in neighbourhood

What about pipes under roads?What about pipes under roads?What do you have?What do you have?What condition are they in?What condition are they in?Are they working as designedAre they working as designedWhat needs to be fixed?What needs to be fixed?When do they need to be fixed? When do they need to be fixed? How much will it cost? How much will it cost?

Now and over next 25 to 50 yearsNow and over next 25 to 50 years

What are they worth?What are they worth?

QuestionsQuestions