ASHA National Office Building 2011 AE Senior Thesis Ryan
Dalrymple 5 th year Structural Option BAE/MAE Advisor: Dr. Thomas
Boothby Photo Courtesy of Boggs & Partners Architects Slide 2
Introduction www.bing.com Building Name: ASHA National Office
Location: 2200 Research Blvd Rockville, MD 20850
Occupant:American-Speech-Language-Hearing Association Occupancy
Type: Office Building Size: 133,870 sq. ft. Number of Stories: 5
stories above grade/2 levels of underground parking Dates of
Construction:April 2006 December 2007 Project Cost:$48,000,000
Presentation Outline Introduction Thesis Objectives/Goals
Structural Depth Floor System Comparison Gravity System Design
ETABS Model Recalculation of Seismic Loads Lateral Design
Foundation Check Construction Management Breadth Cost Analysis
Schedule Analysis Final Summary/Conclusions Slide 3 Introduction
Structural System Gravity System of Office Tower Composite steel
beam floor system 3 NW conc. on 2 18 gauge composite metal deck 3/4
diameter shear studs Typical beam sizes: W21x44, W14x22, W18x35
Columns are W12 and W14 members Gravity System of Subgrade Parking
Structure Two-way flat slab system with drop panels 9 thick slab
with 5 thick drop panels Drop panels typically 7-0x9-0 and
10-0x10-0 5000 psi concrete Typical concrete column sizes: 18x30
and 24x21 Lateral System 4 shear walls/braced frames Shear walls in
subgrade parking structure Braced frames in office tower Foundation
Primarily spread footings Range from 4-0x4-0 to 11-0x11-0 12 to 36
deep Typical Framing Plan Slide 4 Introduction Structural System
Gravity System of Office Tower Composite steel beam floor system 3
NW conc. on 2 18 Ga. composite metal deck 3/4 diameter shear studs
Typical beam sizes: W21x44, W14x22, W18x35 Columns are W12 and W14
members Gravity System of Subgrade Parking Structure Two-way flat
slab system with drop panels 9 thick slab with 5 thick drop panels
Drop panels typically 7-0x9-0 and 10-0x10-0 5000 psi concrete
Typical concrete column sizes: 18x30 and 24x21 Lateral System 4
shear walls/braced frames Shear walls in subgrade parking structure
Braced frames in office tower Foundation Primarily spread footings
Range from 4-0x4-0 to 11-0x11-0 12 to 36 deep Parking Level Framing
Plan Slide 5 Introduction Structural System Gravity System of
Office Tower Composite steel beam floor system 3 NW conc. on 2 18
Ga. composite metal deck 3/4 diameter shear studs Typical beam
sizes: W21x44, W14x22, W18x35 Columns are W12 and W14 members
Gravity System of Subgrade Parking Structure Two-way flat slab
system with drop panels 9 thick slab with 5 thick drop panels Drop
panels typically 7-0x9-0 and 10-0x10-0 5000 psi concrete Typical
concrete column sizes: 18x30 and 24x21 Lateral System 4 shear
walls/braced frames Shear walls in subgrade parking structure
Braced frames in office tower Foundation Primarily spread footings
Range from 4-0x4-0 to 11-0x11-0 12 to 36 deep Typical Framing Plan
Slide 6 Introduction Structural System Gravity System of Office
Tower Composite steel beam floor system 3 NW conc. on 2 18 Ga.
composite metal deck 3/4 diameter shear studs Typical beam sizes:
W21x44, W14x22, W18x35 Columns are W12 and W14 members Gravity
System of Subgrade Parking Structure Two-way flat slab system with
drop panels 9 thick slab with 5 thick drop panels Drop panels
typically 7-0x9-0 and 10-0x10-0 5000 psi concrete Typical concrete
column sizes: 18x30 and 24x21 Lateral System 4 shear walls/braced
frames Shear walls in subgrade parking structure Braced frames in
office tower Foundation Primarily spread footings Range from
4-0x4-0 to 11-0x11-0 12 to 36 deep Partial Foundation Plan Slide 7
Introduction Architecture Building faade of office tower consists
of a window wall system and precast concrete spandrels Plaza level
spaces: Lobby Conference Rooms Pre-function Space Caf and Kitchen
Gym 2 nd 5 th Floor spaces: Offices Cubicles One of the main
architectural themes is curves to mimic the sound waves in the ASHA
logo Pre-function SpaceCurved Glass Curtain Wall www.asha.org Slide
8 Thesis Objectives/Goals Investigate the feasibility of changing
the structural system of the office tower to reinforced concrete
Creates continuity with the concrete parking structure below May
eliminate the need for shear walls/braced frames Presentation
Outline Introduction Thesis Objectives/Goals Structural Depth Floor
System Comparison Gravity System Design ETABS Model Recalculation
of Seismic Loads Lateral Design Foundation Check Construction
Management Breadth Cost Analysis Schedule Analysis Final
Summary/Conclusions Structural Depth Explore two different floor
systems Two-way flat slab w/ drop panels One-way slab and beam
Design gravity system Design floor system Design columns Design
lateral system Determine if gravity members are adequate to resist
gravity loads Design shear walls if needed Explore impact on
foundations Architectural Breadth (Not Presented) Explore impact of
additional columns needed for two- way flat slab floor system
Create layout for Plaza level floor plan Construction Management
Breadth (Presented) Cost Analysis Schedule Analysis Slide 9 Floor
System Comparison Two-way Flat Slab System w/ Drop Panels 9 slab w/
4 drop panels Drop panels generally 9-0x7-0 Concrete compressive
strength of 5000 psi Reinforcing designed to be #5 bars Column
strip and middle strip reinforcing designed in spSlab Presentation
Outline Introduction Thesis Objectives/Goals Structural Depth Floor
System Comparison Gravity System Design ETABS Model Recalculation
of Seismic Loads Lateral Design Foundation Check Construction
Management Breadth Cost Analysis Schedule Analysis Final
Summary/Conclusions spSlab Model Col. Line C spSlab Reinforcement
Diagram Col. Line C Slide 10 Floor System Comparison Two-way Flat
Slab System w/ Drop Panels 9 slab w/ 4 drop panels Drop panels
generally 9-0x7-0 Concrete compressive strength of 5000 psi
Reinforcing designed to be #5 bars Column strip and middle strip
reinforcing designed in spSlab spSlab Model Col. Line C Typical
Framing Plan Two-way Flat Slab Slide 11 Floor System Comparison
spBeam Model Col. Line C spBeam Reinforcement Diagram Col. Line C
One-Way Slab and Beam System 9 slab w/ #5 bars at 6 o.c. Concrete
compressive strength of 5000 psi Flexural and shear reinforcing for
one-way beams designed using spBeam Beams are typically 18 wide and
range from 12 to 26 deep Slide 12 Floor System Comparison Typical
Framing Plan One-way Slab and Beams spBeam Model Col. Line C
One-Way Slab and Beam System 9 slab w/ #5 bars at 6 o.c. Concrete
compressive strength of 5000 psi Flexural and shear reinforcing for
one-way beams designed using spBeam Beams are typically 18 wide and
range from 12 to 26 deep Slide 13 Floor System Comparison One-Way
Slab and Beam System 9 slab w/ #5 bars at 6 o.c. Concrete
compressive strength of 5000 psi Flexural and shear reinforcing for
one-way beams designed using spBeam Beams are typically 18 wide and
range from 12 to 26 deep Typical Framing Plan One-way Slab and
Beams spBeam Model Col. Line C Slide 14 Floor System Comparison
Cost Comparison Two-way flat slab system ~$20.05/sq. ft. One-way
slab and beam system ~$20.29/sq. ft. One-way slab and beam system
ultimately chosen for thesis redesign! Floor Plan Impacts Two-way
flat slab system 25 additional columns One-way slab and beam system
No additional columns Plaza Level Floor Plan Slide 15 Gravity
System DesignPresentation Outline Introduction Thesis
Objectives/Goals Structural Depth Floor System Comparison Gravity
System Design ETABS Model Recalculation of Seismic Loads Lateral
Design Foundation Check Construction Management Breadth Cost
Analysis Schedule Analysis Final Summary/Conclusions Beam layout
created Beam and column widths generally kept the same for
constructability Four transfer girders required, which were
designed using spBeam Typical Framing Plan Slide 16 Gravity System
Design Column Design Columns designed using spColumn Columns
spliced once at level 4 Typical column sizes below splice:
Interior: 18x24 in Exterior: 18x21 in Typical column sizes above
splice: Interior: 18x20 in Exterior: 18x18 in Slide 17 Gravity
System Design Column Design Columns designed using spColumn Columns
spliced once at level 4 Typical column sizes below splice:
Interior: 18x24 in Exterior: 18x21 in Typical column sizes above
splice: Interior: 18x20 in Exterior: 18x18 in Slide 18 ETABS Model
The self-weight of the columns and beams is accounted for in the
model Rigid end zones are applied to all beams with a reduction of
50% The slabs are considered to act as rigid diaphragms The
self-weight of the slab is applied as an additional area mass on
the rigid diaphragm P- effects are considered The moment of inertia
for columns = 0.7Ig The moment of inertia for beams = 0.35Ig The
compressive strength of all concrete is 5000 psi Presentation
Outline Introduction Thesis Objectives/Goals Structural Depth Floor
System Comparison Gravity System Design ETABS Model Recalculation
of Seismic Loads Lateral Design Foundation Check Construction
Management Breadth Cost Analysis Schedule Analysis Final
Summary/Conclusions Slide 19 Recalculation of Seismic Loads
Building weight and seismic loads calculated by hand R = 3.0 for
ordinary concrete moment frame Fundamental periods obtained from
ETABS along principle axes exceeded C u T a C u T a was used as the
design period to calculate seismic loads Veritical Distribution of
Seismic Forces Floorwxwx h x (ft)w x h x ^kC vx FxFx
Parking3007.710.065801.00.0155.3k Plaza2960.020.0163935.90.03713.3k
2nd3354.535.0393265.00.09032.0k 3rd3339.948.5606217.70.13849.3k
4th3294.062.0830852.90.19067.5k 5th3191.775.51048252.40.23985.2k
Roof3105.989.01271638.10.290103.4k Sum4379963.01.000356.1k
Presentation Outline Introduction Thesis Objectives/Goals
Structural Depth Floor System Comparison Gravity System Design
ETABS Model Recalculation of Seismic Loads Lateral Design
Foundation Check Construction Management Breadth Cost Analysis
Schedule Analysis Final Summary/Conclusions Slide 20 Lateral Design
Drift and Displacement Check Allowable seismic story drift for a
building in occupancy category II is 0.02h sx Accepted standard for
total building displacement for wind loads is L/400 Presentation
Outline Introduction Thesis Objectives/Goals Structural Depth Floor
System Comparison Gravity System Design ETABS Model Recalculation
of Seismic Loads Lateral Design Foundation Check Construction
Management Breadth Cost Analysis Schedule Analysis Final
Summary/Conclusions Slide 21 Lateral Design Drift and Displacement
Check Allowable seismic story drift for a building in occupancy
category II is 0.02h sx Accepted standard for total building
displacement for wind loads is L/400 Wind Story Displacement N-S
Direction FloorDisplacement (in)Allowable Displacment (in)Okay? PH
Roof1.4913.150Yes Roof1.4432.670Yes Fifth1.3432.265Yes
Fourth1.1461.860Yes Third0.8661.455Yes Second0.5101.050Yes
Plaza0.1010.600Yes Parking0.0000.300Yes Wind Story Displacement E-W
Direction FloorDisplacement (in)Allowable Displacment (in)Okay? PH
Roof1.5643.150Yes Roof1.5602.670Yes Fifth1.3422.265Yes
Fourth1.1411.860Yes Third0.8531.455Yes Second0.4961.050Yes
Plaza0.1060.600Yes Parking0.0000.300Yes Seismic Story Drift N-S
Direction FloorDisplacement (in)Story Drift (in)Allowable Story
Drift (in)Okay? PH Roof1.5960.0793.84Yes Roof1.5170.1583.24Yes
Fifth1.3590.2493.24Yes Fourth1.1100.3043.24Yes
Third0.8060.3503.24Yes Second0.4560.3663.6Yes Plaza0.090 2.4Yes
Parking0.000 2.4Yes Seismic Story Drift E-W Direction
FloorDisplacement (in)Story Drift (in)Allowable Story Drift
(in)Okay? PH Roof3.8790.3543.84Yes Roof3.5250.3833.24Yes
Fifth3.1420.5613.24Yes Fourth2.5810.7103.24Yes
Third1.8710.8113.24Yes Second1.0600.8363.6Yes Plaza0.224 2.4Yes
Parking0.000 2.4Yes Slide 22 Lateral Design Lateral Design of Beams
and Columns Beams and columns checked to determine if they are
sufficient to resist wind and seismic loads Moments on beams due to
wind and seismic loads obtained from ETABS and input into spBeam
models Axial loads and moments on columns due to wind and seismic
loads input into spColumn Conclusions Shear reinforcing had to be
increased in half of the beams Top reinforcing had to be increased
for a few beams Bottom reinforcing sufficient for all beams Some
edge beams in E-W direction had to be increased in size Typical
Framing Plan Columns did not have to be upsized Reinforcing had to
be increased in some columns Inherent moment resistance of concrete
structure is sufficient to resist lateral loads Shear walls are not
needed! Slide 23 Foundation Check The spread footing at G-3 was
redesigned for additional dead load from concrete structure
Existing 11-0x11-0 footing had to be increased to 12-0x12-0
Reinforcing was designed by hand Punching shear was checked for the
36 deep footing and was found to be adequate Presentation Outline
Introduction Thesis Objectives/Goals Structural Depth Floor System
Comparison Gravity System Design ETABS Model Recalculation of
Seismic Loads Lateral Design Foundation Check Construction
Management Breadth Cost Analysis Schedule Analysis Final
Summary/Conclusions Partial Foundation Plan Slide 24 Construction
Management Breadth Cost Analysis Cost information for existing
structure obtained from Davis Construction Costs obtained from
Davis Construction were adjusted using historical cost indices
found in RS Means Detailed concrete, formwork, and reinforcement
takeoffs were done by hand RS Means used to obtain unit prices for
concrete structure Presentation Outline Introduction Thesis
Objectives/Goals Structural Depth Floor System Comparison Gravity
System Design ETABS Model Recalculation of Seismic Loads Lateral
Design Foundation Check Construction Management Breadth Cost
Analysis Schedule Analysis Final Summary/Conclusions Slide 25
Construction Management Breadth Existing Steel Structure Cost
DescriptionCostAdjusted 2011 Cost Mobilization &
Cranes$299,498.00$326,963 B2 Level$1,596,426.00$1,742,823 B1
Level$1,096,252.00$1,196,782 Plaza Level$341,649.00$372,979 2nd
Floor$62,086.00$67,779 3rd Floor$51,969.00$56,735 4th
Floor$51,969.00$56,735 5th Floor$51,199.00$55,894
Roof$9,852.00$10,755 Total Steel$1,372,852.00$1,498,747
Fireproofing$82,000.00$89,520 Total$5,015,752.00$5,475,712 Concrete
Structure Cost DescriptionCost Mobilization & Cranes326,963 B2
Level1,887,782 B1 Level1,239,164 Plaza Level372,979 Beams462,985
Columns410,621 Slabs1,299,518 Total6,000,013 Cost Comparison
Existing Steel Structure Cost: $5,475,712 Concrete Redesign
Cost:$6,000,013 Slide 26 Construction Management Breadth Schedule
Comparison Presentation Outline Introduction Thesis
Objectives/Goals Structural Depth Floor System Comparison Gravity
System Design ETABS Model Recalculation of Seismic Loads Lateral
Design Foundation Check Construction Management Breadth Cost
Analysis Schedule Analysis Final Summary/Conclusions Total Duration
= 61 daysTotal Duration = 108 days Construction Schedule Existing
Steel Structure Construction Schedule Concrete Redesign Slide 27
Final Summary/Conclusions Presentation Outline Introduction Thesis
Objectives/Goals Structural Depth Floor System Comparison Gravity
System Design ETABS Model Recalculation of Seismic Loads Lateral
Design Foundation Check Construction Management Breadth Cost
Analysis Schedule Analysis Final Summary/Conclusions One-way slab
and beam system was chosen as the floor system for the office tower
The inherent moment resistance of the concrete structure is
sufficient to resist the lateral loads Shear walls are not needed,
which increases the flexibility of the floor plan The concrete
redesign is approximately $500,000 more than the existing steel
structure The construction duration for the concrete redesign is
significantly longer than for steel The concrete redesign is a
viable alternative, although composite steel is most likely the
best structural system Slide 28 Acknowledgements American
Speech-Language-Hearing Association Cagley & Associates Frank
Malits Susan Burmeister Boggs & Partners Architects Mike Patton
Vanderweil Engineers Davis Construction T.J. Sterba Penn State AE
Faculty Dr. Thomas Boothby Dr. Linda Hanagan Dr. Andres Lepage Dr.
Louis Geschwinder Professor Parfitt Professor Holland Thank you for
listening!
