CBD Chemical. Production Building Virginia, USA. Christina DiPaolo Structural Option

Transcription

1 CBD Chemical Production Building Virginia, USA Christina DiPaolo Structural Option

2 CBD Chemical Production Building Virginia, USA N Building Statistics Function/Occupant Type: High Hazard, Chemical Manufacturing Plant Size: 55,000 GSF Stories: Primary Project Team: Dates of Construction: April 2008 January 2009 Cost Information: $125 Million 5 floors, a mezzanine in the first floor, and a penthouse Withheld at request of Engineers and Contractors Project Delivery Method: Design-Bid-Build with a Negotiated Guaranteed Max Contract Site Plan

3 CBD Chemical Production Building Virginia, USA 12 inch x12 inch precast piles Structural Overview Foundation System Tie beams between each column 100-ton capacity each Typical pile cap detail

4 CBD Chemical Production Building Virginia, USA 12 inch x12 inch precast piles Structural Overview Floor System Tie beams between each column 100-ton capacity each Typical pile cap detail 7 ½ inches of normal weight concrete on 3VLI18 roof has 6 inches of normal weight concrete on 3VLI18 Vulcraft 3VLI18 extrusion

5 CBD Chemical Production Building Virginia, USA N inch x12 inch precast piles 22 6 Structural Overview Framing System Tie beams between each column 100-ton capacity each Typical pile cap detail ½ inches of normal weight concrete on 3VLI roof has 6 inches of normal weight concrete on 3VLI Vulcraft 3VLI18 extrusion Third floor framing plan

6 CBD Chemical Production Building Virginia, USA N Structural Overview 27 6 Framing System Third floor framing plan

7 CBD Chemical Production Building Virginia, USA Moment frame in both N-S and E-W N Odd column rotation 22 6 Structural Overview 27 6 Lateral System Third floor framing plan

8 CBD Chemical Production Building Virginia, USA Outline Thesis Goals Structural Depth (MAE Requirement) Construction Management Breadth Conclusions Questions / Comments

9 Structural Depth Construction Management Breadth Outline Optimize the steel for the same assumptions Design a concrete beam and girder system for these constraints Compare steel and concrete systems Analyze impact on deep foundation system Compare cost of two structural systems Compare schedules of two structural systems Thesis Goals Structural Depth (MAE Requirement) Construction Management Breadth Conclusions Questions / Comments A sketchup model of the layout of the one-way slab system.

10 Structural Depth Construction Management Breadth PV/Electrical Breadth Optimize the steel for the same assumptions Design a concrete beam and girder system for these constraints Compare steel and concrete systems Analyze impact on deep foundation system Compare cost of two structural systems Compare schedules of two structural systems MAE Course Material Analyze potential output of photovoltaic panels on roof Size wiring for panels and inverter Cost benefit analysis / payback period A sketchup model of the layout of the one-way slab system. 3D lateral modeling in ETABS from AE 597A

11 Steel Optimization Outline ¾ shear studs spaced 1 o.c. on all beams All beams designed non-compositely Redesign using these shear studs already in place Thesis Goals Structural Depth (MAE Requirement) Construction Management Breadth Conclusions Questions / Comments Structural notes from drawings

12 Steel Optimization ¾ shear studs spaced 1 o.c. on all beams All beams designed non-compositely Redesign using these shear studs already in place Original Design Size # of studs / ft linear feet plf Price/ft Total wt Total Price New Design Size # of studs / ft linear feet plf Price/ft Total wt Total Price W24x $ $ 257, W16x $ $ 151, W12x $ $ 26, W12x $ $ 17, = $ 283, = $ 169, Total Weight Savings: 95,040 lbs Total Cost Savings: $114,156

13 N Floor Dead Loads above Ground Floor 7½ slab on 2VLI18 Deck (NWC) 82 psf Equipment Pads (NWC) 50 psf Steel Framing 18 psf MEP 20 psf Partitions 10 psf Total 180 psf Roof Dead Load 6 slab on 2VLI18 Deck (NWC) 63 psf Equipment Pads (NWC) 50 psf Steel Framing 18 psf MEP 20 psf Roofing 4 psf Misc Dead 5 psf Total 160 psf Loads Gravity Beams Gravity Design Floor Live Load Roof Live Load Live Loads 200 psf 100 psf

14 6 slab based on worst beam spacing Gravity Design All beams are 12x22 for constructability Gravity beams use only #6 and #8 bars Loads Gravity Beams Controlling load case: 1.2D + 1.6L Concrete framing plan Detailing for gravity beam

15 East-West Wind Loads New Earthquake Loads Design Category C Must use at least Intermediate Moment Frame Lateral Design Lateral Loads / Recalculation of earthquake loads k kip-ft R value of 5 North-South Wind Loads k kip-ft k kip-ft

16 ETABS Model Lateral Design Rigid end zones are applied to all beams with a reduction of 50% The slabs are considered to act as rigid diaphragms Lateral Loads / Recalculation of earthquake loads ETABS model All self weights were applied as an additional area mass at the center of gravity of the diaphragms P- effects are considered 3D extruded view of ETABS model The moment of inertia for columns = 0.7Ig The moment of inertia for beams = 0.35Ig A birds eye view of ETABS model

17 Intermediate Moment Frame Positive moment capacity at supports must be at least 1/3 negative moment capacity Lateral Design Lateral Loads / Recalculation of earthquake loads ETABS model Lateral design Positive and negative moment capacity must be at least 1/5 the maximum moment capacity throughout entire length Concrete framing plan

18 Calcs for lateral beam Detailing for lateral beam Concrete framing plan

19 Column Design All columns are 30x30 for ease of construction Controlling Load Case: 1.2D+1.0W+L+.5S Three rebar configurations: (12) #8 (12) #10 (16) #10 spcolumn Output for the columns shaded in purple Concrete framing plan

20 Drift Checks Lateral Design Wind loads were checked against h/400 Earthquake loads were checked against.015 for category III buildings All drifts acceptable Lateral Loads / Recalculation of earthquake loads ETABS model Lateral design Drift checks

21 Foundation Impact Lateral Design Each pile has a 100-ton capacity Lateral Loads / Recalculation of earthquake loads ETABS model Lateral design Drift checks Foundation Impact A simplified approach to the number of piles needed for each column.

22 Original Cost Estimate provided by project engineer Cost Analysis Outline Sum = $5,197,429 Estimated Cost of Concrete Structure Cost information for existing structure obtained from Engineers Detailed concrete, formwork, and reinforcement takeoffs were done by hand RS Means used to obtain unit prices for concrete structure Comparison of steel versus concrete cost performed Thesis Goals Structural Depth (MAE Requirement) Construction Management Breadth Conclusions Questions / Comments

23 Original Cost Estimate provided by project engineer Cost Analysis Sum = $5,197,429 Estimated Cost of Concrete Structure Cost information for existing structure obtained from Engineers Detailed concrete, formwork, and reinforcement takeoffs were done by hand RS Means used to obtain unit prices for concrete structure Comparison of steel versus concrete cost performed Concrete is $1,266, cheaper

24 Schedule Analysis Schedule Information from RS Means One schedule made for each structural system Concrete schedule took 107 days while steel took 223 days Saving over a hundred days may justify the more expensive structure Concrete Schedule Steel Schedule

25 Conclusions Outline The concrete redesign is a viable solution The concrete system is significantly cheaper A longer construction schedule does pose a significant loss in income for CBD Chemical Thesis Goals Structural Depth (MAE Requirement) Construction Management Breadth Conclusions Questions / Comments

26 Outline Thesis Goals Questions / Comments Structural Depth (MAE Requirement) Construction Management Breadth Conclusions Questions / Comments

27 CBD Chemical Production Building Virginia, USA N Structural Overview Framing System 12 inch x12 inch precast piles Tie beams between each column 100-ton capacity each ½ inches of normal weight concrete on 3VLI18 roof has 6 inches of normal weight concrete on 3VLI

28 Steel Optimization ¾ shear studs spaced 1 o.c. on all beams All beams designed non-compositely Redesign using these shear studs already in place Original Design Size # of studs / ft linear feet plf Price/ft Total wt Total Price New Design Size # of studs / ft linear feet plf Price/ft Total wt Total Price W24x $ $ 257, W16x $ $ 151, W12x $ $ 26, W12x $ $ 17, = $ 283, = $ 169, Total Weight Savings: 95,040 lbs Total Cost Savings: $114,156

29 Floor Dead Loads above Ground Floor 7½ slab on 2VLI18 Deck (NWC) 82 psf Equipment Pads (NWC) 50 psf Steel Framing 18 psf MEP 20 psf Partitions 10 psf Total 180 psf Roof Dead Load 6 slab on 2VLI18 Deck (NWC) 63 psf Equipment Pads (NWC) 50 psf Steel Framing 18 psf MEP 20 psf Roofing 4 psf Misc Dead 5 psf Total 160 psf Loads Gravity Beams Gravity Design Floor Live Load Roof Live Load Live Loads 200 psf 100 psf

30 6 slab based on worst beam spacing Gravity Design All beams are 12x22 for constructability Gravity beams use only #6 and #8 bars Loads Gravity Beams Controlling load case: 1.2D + 1.6L

31 East-West Wind Loads New Earthquake Loads Design Category C Must use at least Intermediate Moment Frame Lateral Design Lateral Loads / Recalculation of earthquake loads k kip-ft R value of 5 North-South Wind Loads k kip-ft k kip-ft

32 Lateral Design Lateral Loads / Recalculation of earthquake loads ETABS model Lateral design

33 Column Design All columns are 30x30 for ease of construction Controlling Load Case: 1.2D+1.0W+L+.5S Three rebar configurations: (12) #8 (12) #10 (16) #10 spcolumn Output for the columns shaded in purple Concrete framing plan

34 Drift Checks Lateral Design Wind loads were checked against h/400 Earthquake loads were checked against.015 for category III buildings All drifts acceptable Lateral Loads / Recalculation of earthquake loads ETABS model Lateral design Drift checks

35 Foundation Impact Lateral Design Each pile has a 100-ton capacity Lateral Loads / Recalculation of earthquake loads ETABS model Lateral design Drift checks Foundation Impact A simplified approach to the number of piles needed for each column.

36 Original Cost Estimate provided by project engineer Cost Analysis Sum = $5,197,429 Estimated Cost of Concrete Structure Cost information for existing structure obtained from Engineers Detailed concrete, formwork, and reinforcement takeoffs were done by hand RS Means used to obtain unit prices for concrete structure Comparison of steel versus concrete cost performed Concrete is $1,266, cheaper

37 Schedule Analysis Schedule Information from RS Means One schedule made for each structural system Concrete schedule took 107 days while steel took 223 days Saving over a hundred days may justify the more expensive structure Concrete Schedule Steel Schedule