Wilshire Grand Redevelopment Project
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The document summarizes the Wilshire Grand Redevelopment Project in Los Angeles, California. It describes the project as a 2.1 million square foot, 73-story tower containing 892 hotel rooms, 365,000 square feet of office space, and amenities. Construction highlights include the largest continuous concrete pour in February 2014 and structural design considerations for seismic performance. Pre-loading of upper bracing elements was done to protect the building from permanent deformation due to long-term effects like creep.
Wilshire Grand Redevelopment Project
- 1. www.jacobs.com | worldwide Wilshire Grand Redevelopment Project Project Highlights December 15, 2016
- 3. WILSHIRE GRAND PROJECT • Facility Overview • Construction Highlights • Mass Concrete – Thermal Control • Structural Design – Seismic • Foundation Settlement & Tower Shortening • Pre-Loading of Upper BRBs
- 5. PROJECT LOCATION 900 Wilshire Blvd
- 6. Size: 2,100,000 SF 73-stories 892 key hotel 16 stories of offices – 365,000 SF 7 levels of podium (amenities) 5 levels below grade parking Completion: 2nd Quarter 2017 Owner: Hanjin International Corp/Korean Air Lines Architect: A.C. Martin Partners Structural Engineers: Brandow & Johnston Thornton Tomasetti Project Manager: Martin Project Mgmt General Contractor: Turner
- 7. Level 70 Sky Lobby
- 8. Level 70 Sky Lobby
- 9. Level 70 Bar
- 10. Level 70 Club Lounge
- 11. Level 73 Sky Deck
- 12. Level 5 Pre-function Area
- 13. Level 5 Grand Ballroom
- 14. Level 7 Ballroom
- 15. Level 7 Health & Fitness Club
- 16. Level 7 Shower & Spa
- 17. Level 7 Pool
- 18. View from Figueroa Street
- 19. Level 1 Porte Cochere
- 21. January 2013 21
- 22. May 2013 22
- 23. June 2013 23
- 24. November 2013 24
- 25. The Grand Pour – Feb 15, 2014 25
- 26. Rebar Erection
- 28. EFCO FORM SYSTEM
- 29. June 2014 29
- 30. Year-end 2014 30
- 31. Mid-year 2015 31
- 33. Year-end 2015 33
- 34. Summer 2016 34
- 35. Current – Dec 2016 35
- 36. Mass Concrete - Thermal Control 36
- 37. Mass concrete is the performance definition of such concrete placement, that may develop potentially detrimental high absolute temperature and/or temperature difference due to: • volume and shape • specific amount and rate of heat generation upon hydration and hardening, and • boundary conditions, 37
- 38. The Grand Pour – Feb 15, 2014 38 Saturday, February 15, 2014
- 39. Largest Continuous Concrete Pour 39 Guinness World Record
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- 41. Thermal Control Measures • Cooling Pipe System with Recirculating Chilled Water • Thermal Blanket Insulation • Curing Procedure • QC Temperature Monitoring 41
- 42. • Maximum temperature is limited through proper thermal control measures in order to prevent delayed ettringite formation (DEF). • Maximum temperature difference is limited through proper thermal control measures in order to prevent cracking due to thermal stresses. 42
- 44. SLDE Service Level Design EQ – Frequent occurrence (43-yr return period EQ) – Performance Objective: Designed to stay linear in ‘elastic limit’ – Lateral system rebounds to zero deformation w/ limited arch & struct damage, remains serviceable – Moderate EQ (475-yr return period) damage reparable MCE Maximum Considered EQ Event ‘Major Event’ – Extreme / Severe (2475-yr return period EQ) – Performance Objective: Designed to prevent collapse, mitigate loss of life – Lateral system utilizes ductility, performs numerous cycles ‘plastic yield’ demand PERFORMANCE CRITERIA
- 45. PERFORMANCE BASE DESIGN Designed for known local seismicity – Design consideration: 29 major faults deemed active distance from 0.2 mi. to 46 mi. from site – Nearest quake considered is from Upper Elysian Park Thrust Fault (0.2 mi) – Largest quake considered is from San Andreas Fault (46 mi.) Wind Design – 1700-yr cycle, 160 mph, 3-sec gusts – Wind Tunnel Studies and Computer Simulation – Rigid enough for comfort service-level wind loads – No ‘Tuned Mass Damper’ required, adequate lateral stiffness for comfort
- 46. PERFORMANCE BASE DESIGN Peer Review Approach Favorable over CBC Prescriptive Design – Peer Review Panel members – Establish Performance Objectives with SEOR – PRP Provided Comprehensive Code Compliance Check – Requires full ‘redundant back-up’ system in addition to ‘Core Wall Design’ – Typically results in Conventional Tube Steel Frame with ‘deep girders’ + ‘closer columns’ Benefits Early Collaboration of PRP w/ SEOR = Early Delivery
- 47. Upper Outrigger Trusses – 3 Stories 10 bays-1BRB w/2200 k each Middle Outrigger Trusses – 6 Stories 10 bays-Total 12 BRBs w/800 kips each Lower Outrigger Trusses – 3 Stories 10 bays-Cluster 4-BRBs w/2200 kips each
- 48. Structure: • Concrete Core w/4 Vertical Cells • Steel Floor Frame w/ Composite Metal Deck Structural Statistics: • Steel: 19,000 tons (17.2 million kg) • Concrete: 160,000 cu yds = 16,000 trucks (122K cu m) • Rebar: 70 million lbs = 35,000 tons (31.7 million kg) METRICS – STRUCTURAL OVERVIEW
- 49. LA Live (NYA) BRB’s Specialty structural brace element consisting of an axial force resisting steel core encased by a system that prevents buckling of the steel core.
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- 54. LOWER OUTRIGGER EMBED ERECTED
- 56. Adjustments Due to Foundation Settlement & Tower Shortening 233’ 582’ 869.5’ 1053.5’ 1125.5’ 1210.2’ 1384’ Spire Sail 70th 53rd 28th Top of Mat Foundation Settlement - Differential settlement Core Walls - Reinforced Concrete - Strain due to loading - Shrinkage and Creep Exterior Columns - Built-Up Structural Steel Box Columns - Filled with Concrete - Strain due to loading
- 57. Tower Axial Shortening Design accounted for axial displacements due to: • sequential loading phases during construction • and long term effects (shrinkage and creep) Prevent undue stresses different from design values Perform periodic on‐site measurements 57
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- 60. Adjustments Due to Long Term Creep 233’ 582’ 869.5’ 1053.5’ 1125.5’ 1210.2’ 1384’ Spire Sail 70th 53rd 28th Top of Mat • Single 2,200 kips BRBs • Sensitive to differential movements due to elastic shortening, shrinkage and creep. • Pre-compressing BRBs
- 61. Pre-loading with Hydraulic Jacks 61
- 62. Protect the building from permanent deformation in the 50-yr wind event At 50-yr wind event, the BRB strains are approximately 50% of yield strain Pre-compressing the BRB eliminates permanent deformation after 50 years of creep and shrinkage 62
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- 64. Top of Spire – Prior to Beacon Installation 64
- 65. www.jacobs.com | worldwideJanuary 9, 2017 © Copyright Jacobs Thank you
- 66. Q&A