mgm block a tower overview - Thornton Tomasetti
MGM BLOCK A TOWER OVERVIEW
Presented by:
Kim Lin September 26, 2007
MGM BLOCK A TOWER
§ BACKGROUND § DESIGN & CHALLENGES § CONSTRUCTION § ADDITIONAL SEMINARS WILL COVER TECHNICAL DETAILS.
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SPECIAL THANKS TO THE TEAM § § § § § §
DENNIS POON (Managing Principal) UDOM HUNGSPRUKE LEN JOSEPH MIKE DELASHMIT (Const. Manager) ANGELA HERNANDEZ (Construction) DALLAS DESIGN TEAM: KIM LIN, GREG BIEBERLY COREY GUO JONATHAN NEUBAUER TODD ZIMMERMAN, HEIN NGUYEN
•DESIGN CONCEPT § STRUCTURAL SYSTEM: § CONCRETE SHEAR WALLS. § CONCRETE COLUMNS § POSTTENSIONED FLAT PLATE AT TYPICAL FLOORS. § SLAB AND BEAMS AT CASINO, MECHANICAL FLOORS AND TOWER TOP WITH WINDOW WASHING CRANES § HYBRID SYSTEM AT ELITE FLOORS. § CONCRETE TRANSFER GIRDERS. § HANGING COLUMNS BY USING DYWIDAG BARS. § FOUNDATION SYSTEM: § MAT OR PIER CAP ON DRILLED PIERS.
§ DESIGN TOOLS: § LATERAL SYSTEM (INCLUDING CONCRETE WALL AND LINK BEAM DESIGN): ETABS. § POSTTENSIONED FLOORS: ADAPT 3D MODELER & DECON § SLAB AND BEAM FLOORS: SAFE & PCABEAM § COLUMNS : EXCEL SP READ SHEETS WITH PCACOL SOFTWARE § SHRINKAGE & CREEP: CHICAGO’S SPREADSHEET W/DALLAS UPDATES § FOUNDATION MAT: SAFE
• FOUNDATION SYSTEM § CENTER, NORTH AND SOUTH CORES: 11 TO 13’6” THICK MAT ON DRILLED PIERS § COLUMNS PIER CAPS ON PIERS § SUBGRADE CONDITION: UPPER 75 FEET: MODERATE TO STRONGLY CEMENTED CLAYEY GRAVEL WITH CLICHÉ. UNDERCONSOLIDATED, SATURATED, AND VERY SOFT SOIL DOWN TO 140 FEET. § USED 48” DIAMETER DRILLED PIER TO 120 FEET. § PIER FOUNDATION SETTLEMENT = 45 inches for Tower, 34” for Podium. § IF USE MAT ALONE, SETTLEMENT=12 18 inches DUE TO THE LARGE FOOTPRINT, LOADS WILL BE TRANSFERRED TO DEEPER, SOFTER MATERIAL.
• FOUNDATION SYSTEM (cont.) § TOP OF MAT @ 2111’, BOTTOM OF MAT @ 2099’, WATER TABLE @ 2088’. § PIER AND MAT DESIGN CHALLENGES: ETABS MODEL, USING CQC METHOD, THE SRSS PROCESS YIELDED DIRECTIONLESS OUTPUT FOR FOUNDATION SYSTEM DESIGN. COMPARED THREE METHODS: 1. STATIC EQUIVALENT METHOD (ORIGINAL) 2. READING WALL FORCES & ASSIGNING DIRECTIONS (SAIFUL) 3. SECTIONCUT.
• FOUNDATION SYSTEM (cont.) • § EQX (Center Core): STATIC Mx = 795,133 k’, My=1,312,333 k’ SAIFUL Mx = 148,455 k’, My=2,803,508 k’ SECT CUT Mx = 689,285 k’, My= 605,529 k’ § EQY (Center Core): STATIC Mx=2,531,667 k’, My= 377,142 k’ SAIFUL Mx=1,109,605 k’, My= 602,733 k’ SECT CUT Mx=1,043,068 k’, My= 558,122 k’
• LATERAL SYSTEM
CENTER CORE
SOUTH CORE
NORTH CORE
ETABS MODEL
•LATERAL SYSTEM: § SEISMIC DESIGN § NY PRESENTED BASICS OF SEISMIC DESIGN PARAMETERS USED IN THEIR SD DESIGN IN PREVIOUS SEMINAR. § FOUR WINGS AND CENTER CORE AREA, SD STAGE CHALLENGE WAS TO TUNE ALL CORES AND PLACE SHEAR WALLS WHERE REQUIRED TO REDUCE DIFFERENCES IN LATERAL BEHAVIOR. § CD STAGE: – ADDED PODIUM STRUCTURE. • W/O PODIUM – MASS (WEIGHT) = 1.2 MILLION KIPS. • W/ PODIUM – MASS (WEIGHT) = 1.36 MILLION KIPS (14 %) – USED SEMIRIGID DIAPHRAGM SYSTEM IN LIEU OF RIGID DIAPHRAGM SYSTEM.
• LATERAL SYSTEM (Cont.) § WALL DESIGN AND DIAPHRAGM SHEAR TRANSFER: SHEAR WALLS DROP OFF AT DIFFERENT LEVELS, CONVENTIONAL RIGID DIAPHRAGM WILL CAUSE STRESS SPIKES AT WHERE WALLS DROP OFF. THIS IS SIMILAR TO USING SPRING OR PINNED BASE TO SIMULATE MAT/PILE FOUNDATION.
•LATERAL SYSTEM (Cont.) § SEMIRIGID SYSTEM WAS ADAPTED. SHELL ELEMENTS WERE USED TO MODEL FLOOR SLABS. – DISTRIBUTE HORIZONTAL FORCES BASED ON WALL STIFFNESS. – DISTRIBUTE GRAVITY LOADS. – BOTH SLABS AND COLUMNS NEED TO BE CHECKED FOR COMBINATION WITH SEISMIC INDUCED FLEXTUAL AND SHEAR FORCES. THE RESULTS SHOWED THE COMBINATIONS WITH SEISMIC FORCES DID NOT GOVERN THE SLABS AND GRAVITY COLUMN DESIGN.
• LATERAL SYSTEM (Cont.) § WIND DESIGN: RWDI WIND FORCE RECOMMENDATION: § DUE TO THE COMPLEXITY OF THE BUILDING, WIND LOADS WERE APPLIED AT C. G. OF EACH WING AT EACH FLOOR, PENDING FLOOR GEOMETRY. RWDI PROVIDED A TABLE OF 120 LOAD COMBINATIONS WITH DIFFERENT FACTORS, DIFFERENT DIRECTIONAL SIGNS TO THE NUMERIOUS LOADS. § THIS MADE RUNNING ETABS VERY TIME CONSUMMING WHEN COMBINE WIND LOADS WITH GRAVITY AND SEISMIC LOADS.
ETABS MODEL
LEVEL 01
ETABS MODEL
LEVEL 02
ETABS MODEL
LEVEL 03
FLOOR SYSTEM POUR STRIP #3
POUR STRIP #4
POUR STRIP #1
POUR STRIP #5 POUR STRIP #2
POUR STRIP #6
POUR STRIP #7
ADAPT 3D MODELER
• SLAB DESIGN: § ONE OF THE PRIMARY DIFFERENCE FROM SD TO CD WAS THAT ALL INTERIOR COLUMNS LOCATED ADJACENT TO SHEAR WALLS WERE TAKEN OUT: § ELIMINATED 2 STORY HIGH STEEL TRANSFER GIRDERS AT HARMON LOBBY. § THE DIFFERENTIAL SHORTENING BETWEEN COLUMNS AND SHEAR WALLS WILL BE HARDER TO CONTROL FOR HIGH RISE BUILDINGS. § SLAB THICKNESS (8” VS. 9 ½”..USE L/44 TO L/45 AS A START) § OTHER COORDINATION ITEMS FOR SLAB DESIGN: § FLOOR OPENINGS (MECHANICAL SHAFTS, FCU’S, ROOF DRAINS, STAIR PRESSURIZATION SHAFTS, ETC.) § ADA SHOWER RECESSES. § CURTAIN WALL ANCHOR SIZES & LOCATIONS.
• SLAB DESIGN (Cont.) § NO ELECTRIC CONDUITS INSIDE PT SLAB. § REBAR OPTIMATIZATION: § FAST TRACK? § SIMPLICITY? § OPTIMATIZE WITH VARIOUS LENGTH OF BARS ACROSS THE WIDTH OF A CURVED BUILDING WITH SPAN CHANGES FROM 29 FEET TO 33 FEET.
• SLAB DESIGN (Cont.) § SLAB DEFLECTIONS: § TYPICAL PT BALANCES 75% OF SLAB SELF WEIGHT. § DL DEFLECTION § PT DEFLECTION § DL+PT DEFLECTION § LL DEFLECTION § LONG TERM DEFLECTION § CRITICAL FOR HOTEL WITH GLASS CURTAIN WALLS.
SLAB DEFLECTION DUE TO DEAD WEIGHT
SLAB DEFLECTION DUE TO POSTTENSIONING
SLAB DEFLECTION DUE TO DEAD LOAD AND POSTTENSIONING
SLAB DEFLECTION DUE TO LIVE LOAD
• DESIGN STATISTICS § BUILDING HEIGHT = 600 FEET MAXIMUM (FAA LIMIT IN LAS VEGAS) § BASE FOOTPRINT = 112,000 S.F. § TOTAL SQUARE FOOTAGE ~ 4.5 MIILLION § USABLE FLOOR AREA ~ 3.9 MILLION S.F. § TOTAL CONCRETE VOLUME ~ 250,000 C.Y. § TOTAL POSTTENSIONING CABLES ~ 1,100 MILES (5.8 MILLION FEET LONG – 1,600 TONS) § TOTAL REBAR QUANTITIES ~ 8,000 TONS
•CONSTRUCTION § FOUNDATION CONSTRUCTION: § PIER DRILLING STARTED FROM JANUARY 2006.
§ MAT CONSTRUCTION: § First Mat Poured – Center Core Mat 238 ft Long x 60 ft Max. Wide x 11 ft Deep § Thermalcouples Installed at 6 locations – Three Each Location. § Poured on the 24 th of June, 2006 from 1 AM to 8 AM. § Las Vegas Blvd. was closed to allow for 550 cement trucks to deliver 5,520 cubic yard of concrete.
§ Concrete Pour for the first mat was completed at 8:30 AM § Ambient Temperature during the Pour was 92 degrees. § 6 Hours after the Pour 90 @ BOTTOM, 90 @ MIDDLE, 75 @ TOP
§ 42 Hours after the Pour 145 @ BOTTOM, 175 @ MIDDLE, 160 @ TOP
§ 48 Hours after the Pour – 145 @ BOTTOM, 160 @ MIDDLE, 155 @ TOP § DRAWING SPECIFIED THE MAXIMUM GRADIENT BETWEEN ANY TWO POINTS SHALL NOT EXCEED 77 DEGREES.
UPPER FLOOR CONSTRUCTION
MORE STATISTICS § @ Level 17, Total Concrete Poured = 130,000 cubic yard, which is half of projected total concrete quantity. § @ Level 19, the maximum foundation settlement was measured at 7/8”. @ Level 22, the maximum foundation settlement was measured at 9/16” (….!). The settlement for podium column adjacent to the Tower was 3/8”. Geotechnical Report estimates were 5” and 2” for Tower and Podium respectively.
OTHER CHALLENGES § FAST TRACK: § STRUCTURAL IS 6 MONTH AHEAD OF ARCHITECTURAL & MEP FROM FOUNDATION UP TO LEVEL 25. § 3 MONTH AHEAD FOR LEVELS ABOVE. § COORDINATION ITEMS: § EMBEDS – CRANES, MONORAILS, TRACKS, HANDRAILS, LIFE LINES, LIGHTENING POLES, ETC. § CONDUITS AND PIPING – PENETRATIONS AND SUPPORTS. § VE PROCESS WITH PEER REVIEW. § CURTAIN WALL INSTALLATION: § SLAB DEFLECTIONS. § COLUMN & WALL CREEP AND SHRINKAGE § CONSTRUCTION TOLERANCES .
CONCLUSION • BACKGROUND • DESIGN & CHALLENGES • CONSTRUCTION
Presented by:
Kim Lin September 26, 2007
MGM BLOCK A TOWER
§ BACKGROUND § DESIGN & CHALLENGES § CONSTRUCTION § ADDITIONAL SEMINARS WILL COVER TECHNICAL DETAILS.
``
SPECIAL THANKS TO THE TEAM § § § § § §
DENNIS POON (Managing Principal) UDOM HUNGSPRUKE LEN JOSEPH MIKE DELASHMIT (Const. Manager) ANGELA HERNANDEZ (Construction) DALLAS DESIGN TEAM: KIM LIN, GREG BIEBERLY COREY GUO JONATHAN NEUBAUER TODD ZIMMERMAN, HEIN NGUYEN
•DESIGN CONCEPT § STRUCTURAL SYSTEM: § CONCRETE SHEAR WALLS. § CONCRETE COLUMNS § POSTTENSIONED FLAT PLATE AT TYPICAL FLOORS. § SLAB AND BEAMS AT CASINO, MECHANICAL FLOORS AND TOWER TOP WITH WINDOW WASHING CRANES § HYBRID SYSTEM AT ELITE FLOORS. § CONCRETE TRANSFER GIRDERS. § HANGING COLUMNS BY USING DYWIDAG BARS. § FOUNDATION SYSTEM: § MAT OR PIER CAP ON DRILLED PIERS.
§ DESIGN TOOLS: § LATERAL SYSTEM (INCLUDING CONCRETE WALL AND LINK BEAM DESIGN): ETABS. § POSTTENSIONED FLOORS: ADAPT 3D MODELER & DECON § SLAB AND BEAM FLOORS: SAFE & PCABEAM § COLUMNS : EXCEL SP READ SHEETS WITH PCACOL SOFTWARE § SHRINKAGE & CREEP: CHICAGO’S SPREADSHEET W/DALLAS UPDATES § FOUNDATION MAT: SAFE
• FOUNDATION SYSTEM § CENTER, NORTH AND SOUTH CORES: 11 TO 13’6” THICK MAT ON DRILLED PIERS § COLUMNS PIER CAPS ON PIERS § SUBGRADE CONDITION: UPPER 75 FEET: MODERATE TO STRONGLY CEMENTED CLAYEY GRAVEL WITH CLICHÉ. UNDERCONSOLIDATED, SATURATED, AND VERY SOFT SOIL DOWN TO 140 FEET. § USED 48” DIAMETER DRILLED PIER TO 120 FEET. § PIER FOUNDATION SETTLEMENT = 45 inches for Tower, 34” for Podium. § IF USE MAT ALONE, SETTLEMENT=12 18 inches DUE TO THE LARGE FOOTPRINT, LOADS WILL BE TRANSFERRED TO DEEPER, SOFTER MATERIAL.
• FOUNDATION SYSTEM (cont.) § TOP OF MAT @ 2111’, BOTTOM OF MAT @ 2099’, WATER TABLE @ 2088’. § PIER AND MAT DESIGN CHALLENGES: ETABS MODEL, USING CQC METHOD, THE SRSS PROCESS YIELDED DIRECTIONLESS OUTPUT FOR FOUNDATION SYSTEM DESIGN. COMPARED THREE METHODS: 1. STATIC EQUIVALENT METHOD (ORIGINAL) 2. READING WALL FORCES & ASSIGNING DIRECTIONS (SAIFUL) 3. SECTIONCUT.
• FOUNDATION SYSTEM (cont.) • § EQX (Center Core): STATIC Mx = 795,133 k’, My=1,312,333 k’ SAIFUL Mx = 148,455 k’, My=2,803,508 k’ SECT CUT Mx = 689,285 k’, My= 605,529 k’ § EQY (Center Core): STATIC Mx=2,531,667 k’, My= 377,142 k’ SAIFUL Mx=1,109,605 k’, My= 602,733 k’ SECT CUT Mx=1,043,068 k’, My= 558,122 k’
• LATERAL SYSTEM
CENTER CORE
SOUTH CORE
NORTH CORE
ETABS MODEL
•LATERAL SYSTEM: § SEISMIC DESIGN § NY PRESENTED BASICS OF SEISMIC DESIGN PARAMETERS USED IN THEIR SD DESIGN IN PREVIOUS SEMINAR. § FOUR WINGS AND CENTER CORE AREA, SD STAGE CHALLENGE WAS TO TUNE ALL CORES AND PLACE SHEAR WALLS WHERE REQUIRED TO REDUCE DIFFERENCES IN LATERAL BEHAVIOR. § CD STAGE: – ADDED PODIUM STRUCTURE. • W/O PODIUM – MASS (WEIGHT) = 1.2 MILLION KIPS. • W/ PODIUM – MASS (WEIGHT) = 1.36 MILLION KIPS (14 %) – USED SEMIRIGID DIAPHRAGM SYSTEM IN LIEU OF RIGID DIAPHRAGM SYSTEM.
• LATERAL SYSTEM (Cont.) § WALL DESIGN AND DIAPHRAGM SHEAR TRANSFER: SHEAR WALLS DROP OFF AT DIFFERENT LEVELS, CONVENTIONAL RIGID DIAPHRAGM WILL CAUSE STRESS SPIKES AT WHERE WALLS DROP OFF. THIS IS SIMILAR TO USING SPRING OR PINNED BASE TO SIMULATE MAT/PILE FOUNDATION.
•LATERAL SYSTEM (Cont.) § SEMIRIGID SYSTEM WAS ADAPTED. SHELL ELEMENTS WERE USED TO MODEL FLOOR SLABS. – DISTRIBUTE HORIZONTAL FORCES BASED ON WALL STIFFNESS. – DISTRIBUTE GRAVITY LOADS. – BOTH SLABS AND COLUMNS NEED TO BE CHECKED FOR COMBINATION WITH SEISMIC INDUCED FLEXTUAL AND SHEAR FORCES. THE RESULTS SHOWED THE COMBINATIONS WITH SEISMIC FORCES DID NOT GOVERN THE SLABS AND GRAVITY COLUMN DESIGN.
• LATERAL SYSTEM (Cont.) § WIND DESIGN: RWDI WIND FORCE RECOMMENDATION: § DUE TO THE COMPLEXITY OF THE BUILDING, WIND LOADS WERE APPLIED AT C. G. OF EACH WING AT EACH FLOOR, PENDING FLOOR GEOMETRY. RWDI PROVIDED A TABLE OF 120 LOAD COMBINATIONS WITH DIFFERENT FACTORS, DIFFERENT DIRECTIONAL SIGNS TO THE NUMERIOUS LOADS. § THIS MADE RUNNING ETABS VERY TIME CONSUMMING WHEN COMBINE WIND LOADS WITH GRAVITY AND SEISMIC LOADS.
ETABS MODEL
LEVEL 01
ETABS MODEL
LEVEL 02
ETABS MODEL
LEVEL 03
FLOOR SYSTEM POUR STRIP #3
POUR STRIP #4
POUR STRIP #1
POUR STRIP #5 POUR STRIP #2
POUR STRIP #6
POUR STRIP #7
ADAPT 3D MODELER
• SLAB DESIGN: § ONE OF THE PRIMARY DIFFERENCE FROM SD TO CD WAS THAT ALL INTERIOR COLUMNS LOCATED ADJACENT TO SHEAR WALLS WERE TAKEN OUT: § ELIMINATED 2 STORY HIGH STEEL TRANSFER GIRDERS AT HARMON LOBBY. § THE DIFFERENTIAL SHORTENING BETWEEN COLUMNS AND SHEAR WALLS WILL BE HARDER TO CONTROL FOR HIGH RISE BUILDINGS. § SLAB THICKNESS (8” VS. 9 ½”..USE L/44 TO L/45 AS A START) § OTHER COORDINATION ITEMS FOR SLAB DESIGN: § FLOOR OPENINGS (MECHANICAL SHAFTS, FCU’S, ROOF DRAINS, STAIR PRESSURIZATION SHAFTS, ETC.) § ADA SHOWER RECESSES. § CURTAIN WALL ANCHOR SIZES & LOCATIONS.
• SLAB DESIGN (Cont.) § NO ELECTRIC CONDUITS INSIDE PT SLAB. § REBAR OPTIMATIZATION: § FAST TRACK? § SIMPLICITY? § OPTIMATIZE WITH VARIOUS LENGTH OF BARS ACROSS THE WIDTH OF A CURVED BUILDING WITH SPAN CHANGES FROM 29 FEET TO 33 FEET.
• SLAB DESIGN (Cont.) § SLAB DEFLECTIONS: § TYPICAL PT BALANCES 75% OF SLAB SELF WEIGHT. § DL DEFLECTION § PT DEFLECTION § DL+PT DEFLECTION § LL DEFLECTION § LONG TERM DEFLECTION § CRITICAL FOR HOTEL WITH GLASS CURTAIN WALLS.
SLAB DEFLECTION DUE TO DEAD WEIGHT
SLAB DEFLECTION DUE TO POSTTENSIONING
SLAB DEFLECTION DUE TO DEAD LOAD AND POSTTENSIONING
SLAB DEFLECTION DUE TO LIVE LOAD
• DESIGN STATISTICS § BUILDING HEIGHT = 600 FEET MAXIMUM (FAA LIMIT IN LAS VEGAS) § BASE FOOTPRINT = 112,000 S.F. § TOTAL SQUARE FOOTAGE ~ 4.5 MIILLION § USABLE FLOOR AREA ~ 3.9 MILLION S.F. § TOTAL CONCRETE VOLUME ~ 250,000 C.Y. § TOTAL POSTTENSIONING CABLES ~ 1,100 MILES (5.8 MILLION FEET LONG – 1,600 TONS) § TOTAL REBAR QUANTITIES ~ 8,000 TONS
•CONSTRUCTION § FOUNDATION CONSTRUCTION: § PIER DRILLING STARTED FROM JANUARY 2006.
§ MAT CONSTRUCTION: § First Mat Poured – Center Core Mat 238 ft Long x 60 ft Max. Wide x 11 ft Deep § Thermalcouples Installed at 6 locations – Three Each Location. § Poured on the 24 th of June, 2006 from 1 AM to 8 AM. § Las Vegas Blvd. was closed to allow for 550 cement trucks to deliver 5,520 cubic yard of concrete.
§ Concrete Pour for the first mat was completed at 8:30 AM § Ambient Temperature during the Pour was 92 degrees. § 6 Hours after the Pour 90 @ BOTTOM, 90 @ MIDDLE, 75 @ TOP
§ 42 Hours after the Pour 145 @ BOTTOM, 175 @ MIDDLE, 160 @ TOP
§ 48 Hours after the Pour – 145 @ BOTTOM, 160 @ MIDDLE, 155 @ TOP § DRAWING SPECIFIED THE MAXIMUM GRADIENT BETWEEN ANY TWO POINTS SHALL NOT EXCEED 77 DEGREES.
UPPER FLOOR CONSTRUCTION
MORE STATISTICS § @ Level 17, Total Concrete Poured = 130,000 cubic yard, which is half of projected total concrete quantity. § @ Level 19, the maximum foundation settlement was measured at 7/8”. @ Level 22, the maximum foundation settlement was measured at 9/16” (….!). The settlement for podium column adjacent to the Tower was 3/8”. Geotechnical Report estimates were 5” and 2” for Tower and Podium respectively.
OTHER CHALLENGES § FAST TRACK: § STRUCTURAL IS 6 MONTH AHEAD OF ARCHITECTURAL & MEP FROM FOUNDATION UP TO LEVEL 25. § 3 MONTH AHEAD FOR LEVELS ABOVE. § COORDINATION ITEMS: § EMBEDS – CRANES, MONORAILS, TRACKS, HANDRAILS, LIFE LINES, LIGHTENING POLES, ETC. § CONDUITS AND PIPING – PENETRATIONS AND SUPPORTS. § VE PROCESS WITH PEER REVIEW. § CURTAIN WALL INSTALLATION: § SLAB DEFLECTIONS. § COLUMN & WALL CREEP AND SHRINKAGE § CONSTRUCTION TOLERANCES .
CONCLUSION • BACKGROUND • DESIGN & CHALLENGES • CONSTRUCTION
