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

Introduction Building Name: ASHA National Office Location: 2200 Research Blvd Rockville, MD 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

Introduction Structural System Gravity System of Office Tower Composite steel beam floor system 3 ½” 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 ½” thick drop panels Drop panels typically 7’-0”x9’-0” and 10’-0x10’-0” 5000 psi concrete Typical concrete column sizes: 18”x30” and 24”x21” 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’-0”x4’-0” to 11’-0”x11’-0” 12” to 36” deep Typical Framing Plan

Introduction Structural System Gravity System of Office Tower Composite steel beam floor system 3 ½” 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 ½” thick drop panels Drop panels typically 7’-0”x9’-0” and 10’-0x10’-0” 5000 psi concrete Typical concrete column sizes: 18”x30” and 24”x21” 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’-0”x4’-0” to 11’-0”x11’-0” 12” to 36” deep Parking Level Framing Plan

Introduction Structural System Gravity System of Office Tower Composite steel beam floor system 3 ½” 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 ½” thick drop panels Drop panels typically 7’-0”x9’-0” and 10’-0x10’-0” 5000 psi concrete Typical concrete column sizes: 18”x30” and 24”x21” 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’-0”x4’-0” to 11’-0”x11’-0” 12” to 36” deep Typical Framing Plan

Introduction Structural System Gravity System of Office Tower Composite steel beam floor system 3 ½” 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 ½” thick drop panels Drop panels typically 7’-0”x9’-0” and 10’-0x10’-0” 5000 psi concrete Typical concrete column sizes: 18”x30” and 24”x21” 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’-0”x4’-0” to 11’-0”x11’-0” 12” to 36” deep Partial Foundation Plan

Introduction Architecture Building façade of office tower consists of a window wall system and precast concrete spandrels Plaza level spaces: Lobby Conference Rooms Pre-function Space Café 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

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

Floor System Comparison Two-way Flat Slab System w/ Drop Panels 9” slab w/ 4 ½” drop panels Drop panels generally 9’-0”x7’-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

Floor System Comparison Two-way Flat Slab System w/ Drop Panels 9” slab w/ 4 ½” drop panels Drop panels generally 9’-0”x7’-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

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

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

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

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

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

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

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

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

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 Parking k Plaza k 2nd k 3rd k 4th k 5th k Roof k Sum k 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

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

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 Roof Yes Roof Yes Fifth Yes Fourth Yes Third Yes Second Yes Plaza Yes Parking Yes Wind Story Displacement E-W Direction FloorDisplacement (in)Allowable Displacment (in)Okay? PH Roof Yes Roof Yes Fifth Yes Fourth Yes Third Yes Second Yes Plaza Yes Parking Yes Seismic Story Drift N-S Direction FloorDisplacement (in)Story Drift (in)Allowable Story Drift (in)Okay? PH Roof Yes Roof Yes Fifth Yes Fourth Yes Third Yes Second Yes Plaza Yes Parking Yes Seismic Story Drift E-W Direction FloorDisplacement (in)Story Drift (in)Allowable Story Drift (in)Okay? PH Roof Yes Roof Yes Fifth Yes Fourth Yes Third Yes Second Yes Plaza Yes Parking Yes

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!

Foundation Check The spread footing at G-3 was redesigned for additional dead load from concrete structure Existing 11’-0”x11’-0” footing had to be increased to 12’-0”x12’-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

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

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

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

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

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!