Reinsurance Group of America (RGA) Global Headquarters Natasha - PowerPoint PPT Presentation

Reinsurance Group of America (RGA) Global Headquarters Natasha Beck Structural Option N Faculty Advisor: Heather Sustersic Images courtesy of Gensler & Tom Rolfes

Occupancy: General office and training RGA Global Headquarters Introduction Construction: March 2013 to September 2014 Delivery: Design-Build Project Team: 2 Parking Levels Size: 405,000 GSF Introduction General Contractor: Clayco 5 Office Levels per Tower Cost: Approx. $150 million Problem Statement & Solution Green Roof Garden Breadth Architect: Gensler Structural Depth Structural Engineer: Uzun & Case Gravity System Lateral System Civil Engineer: Stock & Associates Construction Breadth Results Landscape Architect: Forum Studio Conclusions Acknowledgements Lighting Consultant: Randy Burkett Lighting Design MEP/Fire Protection: Environmental Systems Design Model courtesy of Gensler & Tom Rolfes

RGA Global Headquarters Problem Statement & Solution +172% Dead +355% Live +112% Dead Scenario: +118% Live Introduction Owner has decided to incorporate a green roof Problem Statement & Solution garden that is open to RGA’s employees Green Roof Garden Breadth Structural Depth Gravity System Thesis Study Goals: Lateral System Construction Breadth Results 1. Interdisciplinary green roof design Conclusions 2. Revise gravity and lateral systems under Acknowledgements green roof loading 3. Explore cost and schedule impact Model courtesy of Gensler & Tom Rolfes

RGA Global Headquarters Green Roof Garden Breadth Introduction Problem Statement & Solution Green Roof Garden Breadth Sedums Garden Plants Wildflower Plants Structural Depth Gravity System Lateral System Construction Breadth Results Conclusions Acknowledgements

RGA Global Headquarters Green Roof Garden Breadth Introduction Interdisciplinary Design Requirements: Problem Statement & Solution Green Roof Garden Breadth 1. Reasonable initial cost Structural Depth 2. Amenity seating area Gravity System Lateral System 3. Tenant circulation Construction Breadth Results 4. Low maintenance Conclusions Acknowledgements 5. Architectural lines are uninterrupted N Layout

6” Growing Medium: Structural Load Cases RGA Global Headquarters Green Roof Garden Breadth 4” Growing Medium: Dead: 68 PSF Roofmeadow Type V System Water Live: 34 PSF Dead: 53 PSF Roof Live: 20 PSF Water Live: 26 PSF Introduction Problem Statement & Solution Roof Live: 20 PSF Public Live: 100 PSF Green Roof Garden Breadth Structural Depth Snow: 22 PSF Snow: 22 PSF Gravity System Wind: -21 PSF Wind: -21 PSF Lateral System Construction Breadth Results Conclusions Dead: +112% Dead: +172% Acknowledgements Live: +118% Live: +355%

RGA Global Headquarters Structural Depth Existing Gravity System Built Up Plate Cambered Truss System Girder Introduction Level 02 Problem Statement & Solution Green Roof Garden Breadth From C.D. Structural Depth Gravity System Roof Framing N Lateral System Construction Breadth Results Conclusions Acknowledgements From C.D. Truss T1 From C.D. Truss T2

RGA Global Headquarters Structural Depth From C.D. Introduction Problem Statement & Solution Truss T1: Green Roof Garden Breadth Roof Reactions Structural Depth Gravity System Floor Gravity Lateral System Reactions on T2 Construction Breadth Results Conclusions Acknowledgements Deflection < ¾”

RGA Global Headquarters Structural Depth From C.D. Introduction Problem Statement & Solution Truss T2: Green Roof Garden Breadth Roof Reactions Structural Depth Gravity System T1 Reactions Lateral System Floor Gravity Construction Breadth Results Conclusions Reactions to Roof Acknowledgements Deflection < ¾”

RGA Global Headquarters Structural Depth From C.D. Introduction Problem Statement & Solution Roof Truss: Green Roof Garden Breadth T2 Reactions Structural Depth Gravity System Reactions to BFs Lateral System Construction Breadth Results Deflection < 1.73” Conclusions Acknowledgements

RGA Global Headquarters Structural Depth Existing Lateral System Two Stage Procedure Introduction Problem Statement & Solution Green Roof Garden Breadth Structural Depth Gravity System Lateral System Steel Braced Frames Construction Breadth Results Conclusions Concrete Shear Walls Acknowledgements Model courtesy of Scope From C.D. Gensler & Tom Rolfes

RGA Global Headquarters Structural Depth Concentrically Braced Frames Existing Layout: HSS Braces Introduction R = 3 Problem Statement & Solution From C.D. Green Roof Garden Breadth N Structural Depth Gravity System Lateral System Construction Breadth Results Conclusions Acknowledgements From C.D. BF 5 & 6 BF 7 & 8

RGA Global Headquarters Structural Depth ETABS Model 5000 4000 Seismic Force Adjustments: Introduction 3000 Problem Statement & Solution Assume Seismically Detailed R = 7 HSS 2000 Green Roof Garden Breadth BRB Two stage procedure impact Structural Depth 1000 Gravity System 0 Lateral System Base Shear Comparison (k) Construction Breadth Results Conclusions New Response New Period New Office Base Shear New Ratio New Structure Base Shear Acknowledgements R = 7 Ta = 8.42 sec. V = 323 k 1.75 V = 1552 k • As-Built: R = 3 • As-Built: 0.561 s • As-Built: V = 3338 k • As-Built: 1.0 • As-Built: V = 4235 k

BF 5 & 6 RGA Global Headquarters Structural Depth Member Sizes & Code Check Controlling load combination: (1.2 + 0.2S DS ) D + ρ Q E + L + 0.2S Introduction From ASCE 7-05 12.4.2.3 Problem Statement & Solution Green Roof Garden Breadth Structural Depth Gravity System • SDC C • R = 7 Lateral System Construction Breadth Results • I = 1.25 • C d = 5.5 Conclusions Controlling Frame STARBRB-36.0 = • ρ = 1.0 • F y = 46 ksi Acknowledgements Design Forces Buckling-Restrained • S DS = 0.400 For Preliminary Brace with 36 sq. in. Sizing steel core area

RGA Global Headquarters Construction Breadth Square Foot Cost Comparison Roof System & Supporting Structure Cost Summary: Sq. Ft. Cost As-Built Green Roof As-Built Project : $1,717,700 Introduction Problem Statement & Solution $60.38 per SF $0.00 $50.00 $100.00 $150.00 $200.00 $250.00 Green Roof Garden Breadth Green Roof : $5,774,600 Structural Depth Gravity System $202.97 per SF Schedule Activity Duration Comparison Lateral System Construction Breadth Results Includes: As-Built Conclusions Truss Framing Acknowledgements • 10% Overhead and Profit • Location Roof Framing Green Roof • 4% Missouri Sales Tax • Time Roof System 0 10 20 30 40 50 60 70 80 • 5% Contingency Activity Duration (Days)

Thesis Study Conclusions: RGA Global Headquarters Conclusions • Green roof designed with interdisciplinary approach • Implications on gravity and lateral systems System Conclusions: • considered and minimized where possible Green roof garden system is feasible Introduction • Problem Statement & Solution • Accounted for cost and schedule factors Cantilever impact minimized Green Roof Garden Breadth • Buckling-restrained braces work, but are not Structural Depth Gravity System most efficient in this application Lateral System • Cost and schedule increase reasonable, but Construction Breadth Results Conclusions final decision rests in the owner’s hands Acknowledgements Model courtesy of Gensler & Tom Rolfes

RGA Global Headquarters Acknowledgements Introduction Heather Sustersic Problem Statement & Solution Green Roof Garden Breadth Ruby+Associates Structural Depth Perry Esslinger & Tom Rolfes with Clayco Gravity System Lateral System Family, Friends, God Construction Breadth Results Conclusions Acknowledgements Images courtesy of Gensler & Tom Rolfes

RGA Global Headquarters Questions? Introduction Problem Statement & Solution Green Roof Garden Breadth Structural Depth Gravity System Lateral System Construction Breadth Results Conclusions Acknowledgements Model courtesy of Gensler & Tom Rolfes