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Seattle Temple: Bearing Column Replacement. A BYU Civil and Environmental Engineering Capstone Project by : Charles Connors, Andrew Luna, and Jonathon Archer Parallel Engineering. W here is the column we are replacing?. Existing Condition. - PowerPoint PPT Presentation
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A BYU Civil and Environmental Engineering Capstone Project by: Charles Connors, Andrew Luna, and Jonathon Archer Parallel Engineering
Seattle Temple:Bearing Column Replacement
Where is the column we are replacing?
Existing ConditionThe column is currently located in a less than ideal spot.
The ProblemThe chapel in the baptistry of the LDS Seattle Temple has large column in the center of the view to the font.
View from the chapel
Existing Condition
Proposed Solution #1: Short SpanOur proposed solution is to move the column load out to two smaller columns six feet in from the outside walls.
View from the chapel
Fourth Points
Proposed Solution #2: Long SpanThe column might also be supported by a much heavier beam that would span from wall to wall.
View from the chapel
Full Span
Short Span 3D View
Column Loads The un-factored loads on the structure are:
Dead: 135.7 kips
Live: 81.5 kips
Snow: 2.3 kips
Rain: 12 kips
Earthquake (-Y): 1557 kips
Earthquake (+Y): 1387 kips
A shear wall above the column is imposing very large earthquake loads. These loads obviously govern our design. Calculations of these loads are shown on the following slides.
Seismic Loading Based on the pertinent seismic design criteria, we calculated and distributed a base shear force. The base shear force approximates the effects of a seismic event on the building. Story
Wx (kip)
hx (feet)
Wx*hx^k (for k=1.03)
Fx (kip)
Vx (kip)
Roof 2725 84 258522 1199 1199Mechanical 2281 72 184701 857 2055
Level 4 3495 60 234658 1088 3144Level 3 3655 45 182602 847 3990Level 2 5629 30 185405 860 4850
Ground Floor 6028 15 97402 452 5302Sum 23813 Sum 1143291
Diaphragm Distribution Based on the stiffness of the individual wall segments, the earthquake forces were distributed to each of the walls. The diaphragm was assumed to be rigid and torsional moments were included in the analysis.
The shear wall in question had a maximum shear force of 475 kips.
Xstart (ft) Xend (ft) w (K/ft) Xstart (ft) Xend (ft) w (K/ft)0 164 29.57317073 0 194 27.32989691
A.T.? Point Load (k) Length X(ft) P (K)Y 194 10152
Load Direction Length Y(ft) A.T. OffsetY 89.83392435 89.8339243 142 9.7
Wall #Wall Stiffness
(K/in)Orientation
of wallCOF X
CoordinateCOF Y
CoordinateDist. From Datum to Center of Wall (ft)
Xr (ft) Fi (kip)Moment @ C.R. (K-ft)
1 4780 Y 163 48 163 86.1 475 136798.42 4780 Y 163 116 163 Yr (ft) 475 Direction3 10920 Y 194 18 194 71.1 11144 10920 Y 194 124 194 1114
Clockwise (-)
Dist Load 1 Dist Load 2
"COF" Center of Frame
Global Structure
Individual Walls
Center of Mass (x,y)
Shear Wall Overturning MomentThe compression/tension reactions required to prevent the shear wall from overturning are calculated to be 1557 kips. By summing moments about bottom right corner;
𝑅=𝑉 ×15 ′
14.5 ′=491𝑘𝑖𝑝
Total earthquake effects are:
𝑃𝑈= (1.2+0.2𝑆𝐷𝑆 )𝐷+Ω𝐸+𝐿=1557𝑘𝑖𝑝
Using Load combinations #5&6 our total column forces are:
𝐸h=491𝑘𝑖𝑝 𝐸𝑉=0.2𝑆𝐷𝑆∗𝐷=24 𝑘𝑖𝑝𝐸=𝐸h+𝐸𝑉=515𝑘𝑖𝑝
𝑃𝑈𝑝𝑙𝑖𝑓𝑡=(0.9−0.2𝑆𝐷𝑆)𝐷+Ω𝐸=1387𝑘𝑖𝑝
Beam OptionsPROPOSED SOLUTION #1: SHORT SPAN
Beam Length: 13 ft. Beam Depth: 26.5 in. Beam Weight: 5.4 kips. Service Load Deflection: 0.04 in. Deflection ratio: L/3900
PROPOSED SOLUTION #2: LONG SPAN Beam Length: 29 ft. Beam Depth: 26.5 in. Beam Weight: 23 kips. Service Load Deflection: 0.281 in. Deflection ratio: L/1200
Existing Column to Beam Connection
A connection with adequate tension capacity was designed to connect the new beam to the existing column from above.
Foundation Column & FootingColumn Size:
24 in. X 24 in. X 12 ft.Footing Size:
7.0 ft. X 7.0 ft. X 2 ft. 3 in.
Removing Existing Wall Foundation
Constructability – Long Span (29ft.)
The long beam option cannot be maneuvered into place without significant changes to the laundry room.
Removing walls adjoining the engineer’s offices is not an option because they contain concrete shear walls.
Baptistry
Constructability – Short Span (13ft.)
The shorter beam option can be maneuvered into place simply by moving the large tables in the laundry room. It is also 16 kips lighter.
Cost Estimate - Short SpanCategory Cost Man Hours
Demolition & Protection $51,200 320
Concrete $53,165 424
Metals $77,503 340
Openings & Finishes $51,900 328
Fire Suppression, Plumbing, HVAC, & Electrical $34,200 456
Earthwork $166,800 664
Total $434,768 2532
Questions?
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