Seattle Temple:
Bearing Column
Replacement
A BYU Civil and Environmental Engineering Capstone Project by:
Charles Connors, Andrew Luna, and Jonathon Archer
Parallel Engineering
Where is the
column we are
replacing?
Existing Condition
The column is currently located in a less than ideal spot.
Existing Condition
View from the chapel
The Problem
The chapel in the baptistry of the LDS Seattle Temple has large column in the center of the view to the font.
Fourth Points
View from the chapel
Proposed Solution #1: Short Span
Our proposed solution is to move the column load out to two smaller columns six feet in from the outside walls.
Full Span
View from the chapel
Proposed Solution #2: Long Span
The column might also be supported by a much heavier beam that would span from wall to wall.
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.
Wx
hx
Wx*hx^k
Fx
Story
(kip) (feet) (for k=1.03) (kip)
Roof
2725
84
258522
1199
Mechanical 2281
72
184701
857
Level 4
3495
60
234658
1088
Level 3
3655
45
182602
847
Level 2
5629
30
185405
860
Ground Floor 6028
15
97402
452
Sum 23813
Sum 1143291
Vx
(kip)
1199
2055
3144
3990
4850
5302
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)
0
A.T.?
Y
Global Structure
Dist Load 1
Dist Load 2
Xend (ft)
w (K/ft)
Xstart (ft) Xend (ft)
w (K/ft)
164
29.57317073
0
194
27.32989691
Point Load (k)
Length X(ft)
194
Load Direction Center of Mass (x,y) Length Y(ft)
Y
89.83392435 89.8339243
142
P (K)
10152
A.T. Offset
9.7
Individual Walls
Wall #
1
2
3
4
"COF" Center of Frame
Wall Stiffness Orientation
COF X
COF Y
Dist. From Datum to
(K/in)
of wall
Coordinate Coordinate Center of Wall (ft)
4780
Y
163
48
163
4780
Y
163
116
163
10920
Y
194
18
194
10920
Y
194
124
194
Xr (ft)
Fi (kip)
86.1
Yr (ft)
71.1
475
475
1114
1114
Moment @
C.R. (K-ft)
136798.4
Direction
Clockwise (-)
Shear Wall Overturning Moment
The compression/tension reactions required to
prevent the shear wall from overturning are
calculated to be 1557 kips. By summing
moments about bottom right corner;
𝑉 × 15′
𝑅=
= 491 𝑘𝑖𝑝
14.5′
Total earthquake effects are:
𝐸ℎ = 491𝑘𝑖𝑝
𝐸𝑉 = 0.2𝑆𝐷𝑆 ∗ 𝐷 = 24𝑘𝑖𝑝
𝐸 = 𝐸ℎ + 𝐸𝑉 = 515𝑘𝑖𝑝
Using Load combinations #5&6 our total
column forces are:
𝑃𝑈 = 1.2 + 0.2𝑆𝐷𝑆 𝐷 + Ω𝐸 + 𝐿 = 1557 𝑘𝑖𝑝
𝑃𝑈𝑝𝑙𝑖𝑓𝑡 = 0.9 − 0.2𝑆𝐷𝑆 𝐷 + Ω𝐸 = 1387 𝑘𝑖𝑝
Beam Options
PROPOSED SOLUTION #1: SHORT SPAN
PROPOSED SOLUTION #2: LONG SPAN
Beam Length:
Beam Depth:
Beam Weight:
Service Load Deflection:
Deflection ratio:
Beam Length:
Beam Depth:
Beam Weight:
Service Load Deflection:
Deflection ratio:
13 ft.
26.5 in.
5.4 kips.
0.04 in.
L/3900
29 ft.
26.5 in.
23 kips.
0.281 in.
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 & Footing
Column 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 Span
Category
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?