JW Marriott
OUTLINE
Greg Kochalski
Introduction
Existing Structure
Floor System
Lateral System
Structural Redesign
Floor System
Lateral System
Architectural Redesign
Cost Analysis
Conclusions/Recommendations
Introduction
Project Information
•24 story Marriott signature series
Hotel
•Located along the Grand River in
downtown Grand Rapids, MI
•340 Rooms
•376,000 sq. ft.
•Amenities include restaurant, lounge,
business center, fitness center, and spa
•Stylistic architecture with reflective
glass cladding
•Open Air Atrium
•Heated Helipad
JW Marriott
Greg Kochalski
Introduction
Site Plan
Downtown
Grand Rapids
JW Marriott
Greg Kochalski
JW Marriott
Introduction
Greg Kochalski
Project Team
owner- Alticor inc.
Architect- Goettsch Partners and
Beta Design Group
Structural- Thornton Tomasetti Engineers
Contractor- Pepper Construction and
Rockford Construction
MEP- Cosentini Associates
JW Marriott
OUTLINE
Greg Kochalski
Introduction
Existing Structure
Floor System
Lateral System
Structural Redesign
Floor System
Lateral System
Architectural Redesign
Cost Analysis
Conclusions/Recommendations
Existing Structure
JW Marriott
Greg Kochalski
Foundation
•200 ton micro piles
•Pile caps located along the
perimeter and beneath the core
•4-7 micro piles per group
Existing Structure
JW Marriott
Greg Kochalski
Floor System
•Flat Plate R.C.
•Short spans- 17 ft.
•One way action
•Typical bay approx 17x35 ft
•7.5 in. Slab
• f’c = 5700 psi
•Blade-Columns located along
perimeter
•Transfer girders at levels 3-5
Eccentric loading requires heavy torsional
reinforcing in beam
Existing Structure
JW Marriott
Greg Kochalski
Blade-Columns
•Reduce spans
•Limit slab thickness
•Maximize patron views
•Fit within interior partitions
•Boundary confinement at
edges
Typical Floor with Radial
Columns
Confinement
Typical bay
Existing Structure
JW Marriott
Greg Kochalski
Lateral System
•Two pairs of shear walls
•F’c varies from 10 ksi to 6ksi
•Boundary elements for increased inertia in
east-west
•12 in. thick in both directions
Heavy confinement
in boundary elements
JW Marriott
OUTLINE
Greg Kochalski
Introduction
Existing Structure
Floor System
Lateral System
Structural Redesign
Floor System
Lateral System
Architectural Redesign
Cost Analysis
Conclusions/Recommendations
JW Marriott
Structural Redesign
Greg Kochalski
Proposal Summary
Design Goals
•Relocation to Monterey, CA
•Achieve desired non-linear
response
•New lateral system
•New Post tension floor system
•Use updated building code
Building Codes
Grand Rapids
Monterey
•MBC 3003 (IBC 2003)
•IBC 2006
•ACI318 2002
•ACI318 2002
•ASCE7 2002
•ASCE7 2005
•Avoid pitfalls of peer
review
•Limit vertical walls to
<3.0% of floor area
JW Marriott
Post Tension System
Greg Kochalski
Characteristics
•Typical span = 35 ft.
•9.5 in. PT flat plate (l/45)
•Class U system
•Balance 85% dead load
•½ in. 270 ksi strands
•F’c = 4000 psi
PT Floor Loads
Labeling Scheme
Design
Loads (psf)
ASCE 7
(psf)
Dead
20
20
Live
40
40
Post Tension System
JW Marriott
Greg Kochalski
JW Marriott
Post Tension System
Large banded tendons
Greg Kochalski
Small banded tendons
JW Marriott
Post Tension System
Greg Kochalski
Average Stresses
F Mn

A S
Mn
F
 225 psi ,
  442 psi ,79 psi 
A
S
f  217  6 f 'c
f 
 667  0.3 f 'c
 79  2 f 'c
 529
Slab Deflections
Span
Deflection
(in)
Deflection
Equivalent
AB
0.268
L/1150
CD
0.361
L/1150
*9.5 in. PT flat slab works*
JW Marriott
Lateral System
Greg Kochalski
Nonlinear Response
•Force dissipation mechanism
ensures integrity
•Plastic hinging in beams, walls
approach yielding
•Detailed for proper ductility
•Even deformations over height
Peer Review
•256 ft exceeds 240 ft height limit
•Requires “code equivalent
performance”…
•Inherent uncertainties when
interpreting code
JW Marriott
Lateral System
Greg Kochalski
Analysis Methods
•Equivalent lateral force method
•Manual calculations
•Etabs
•Modal response (dynamic) analysis
•Etabs
Spectral Response Parameters
•Sds=0.97
•O.C.=II
•Sd1=0.53
•R=5.0
•S.D.C.= D
•Cd=4.5
•S.C. = C
JW Marriott
Lateral System
Etabs Cases & Combinations
•Static analysis (accidental torsion)
•EXZ1- ecc in x, cw moment
•EXZ2- ecc. In –x, ccw moment
•EYZ1
•EYZ2
•Dynamic analysis (member forces)
•XSPECF
•YSPECF
•Dynamic analysis (Displacements)
•XSPECD
•YSPECD
Greg Kochalski
Scale Factors
JW Marriott
Lateral System
Greg Kochalski
Pier and Spandrel Labeling
JW Marriott
Lateral System
Greg Kochalski
Coupling Beams
Interpreting the output
Influence…
3
•Period
Period (s), V (normalized)
2.5
•Shear (in walls)
•displacements
Cracked section
Ieffective 
Period
1.5
Vnormalized
1
0.5
0.2
 Igross
2
1  3h / ln 

2

Ultimate shear
Vu    8.0 f ' c  bd
0
0.00
0.20
0.40
0.60
0.80
Ie
Ie
0.10
0.16
0.5
0.75
Varying Ieff
Vmax
Vnorm
Period
189
232
317
340
2.76
2.425
1.99
1.90
0.814655
1
1.366379
1.465517
JW Marriott
Lateral System
Ultimate Shear
Determined Group, and will be the
Maximum of
•0.8Vmax
•Vaverage
Detailing
Reinforcing must ensure
•Proper Ductility
•Failure in moment, not shear
Greg Kochalski
Level
Roof
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2 Mezz
2
Coupling Beam Ultimate Shear
Shears
Design Group Shears
Shear
0.8 Vmax
Vaverage
0.8 Vmax
Vaverage
(K)
(K)
(K)
(K)
(K)
90
111
113
122
122
122
122
121
131
142
152
162
171
179
161
161
182
182
187
194
201
208
214
220
186
221
225
229
232
186
213
231
228
220
186
205
205
181
163
Lateral System
JW Marriott
Greg Kochalski
JW Marriott
Lateral System
Greg Kochalski
Displacement
<2.0% Height (code)
<1.0% Height (imposed)
0.01H = 30 in.
Max Displacement
16.6 in. (x)
21.4 in. (y)
y
x
X direction
Y direction
JW Marriott
Lateral System
Greg Kochalski
Displacement
Roof
Max Displacement
Story 23
Story 21
16.6 in. (x)
Story 19
21.4 in. (y)
Story 17
Level
Story 15
delta y
Story 13
delta x
Interpreting output
Story 11
•Beam action in Y
Story 9
•Frame action in X
Story 7
Story 5
Story 3
y
2nd
0.00
5.00
10.00
15.00
Inches
20.00
25.00
x
JW Marriott
Lateral System
Greg Kochalski
Shear Walls
Design Criteria
Direct Shear
Flexure
•Distributes by area
•Distributes by inertia
•Limit shear to:
•Reinforce to resist tension
Vu   4.0 f 'c  t  l
JW Marriott
Lateral System
Greg Kochalski
Direct Shear
Vu   4.0 f 'c  t  l
Pier 3 :
1100 k    3 . 59
Pier 4 & 5 :
343 k    2 . 24
f ' c  Av ,
where Av 4 / 5  18 . 67 ft 2
Pier 6 :
876 k    4 . 11
f ' c  Av ,
where Av 6  26 . 0 ft 2
Pier 7 & 8 :
350 k    3 . 78
f ' c  Av ,
where Av 7 / 8  * 19 . 5 ft 2
f ' c  Av ,
where Av 3  37 . 33 ft 2
* Av 7 / 8  9 . 77 ft 2  cos( 33  )  12 . 2 ft 2  cos( 22  )
JW Marriott
Lateral System
Greg Kochalski
Interpreting the Output
Av shown in blue
Theoretical
Av (ft2)
26
Kv
0.7
DFv
0.21
37.3
1.0
0.29
Etabs Output (YSPECF)
VOP
876 1100
DFOP
0.22 0.28
37.3
1.0
0.29
26
0.7
0.21
1100
0.28
876
0.22
JW Marriott
Lateral System
Greg Kochalski
Flexure
Reinforce Tension Areas
where E v  0.2 S DS D , S DS  0.97 , and L  0
•PCA column
ASCE7 then becomes :
•Load cases derived from
ASCE7
My
ASCE7 : 0.9 D  0.5 L  1.0 E  1.0 E v
Mx
1 0.7 D  1.0 E x  0.3E y
2 0.7 D  1.0 E x  0.3E y
3 0.7 D  1.0 E x  0.3E y
4 0.7 D  1.0 E x  0.3E y
5 0.7 D  0.3E x  1.0 E y
6 0.7 D  0.3E x  1.0 E y
7  0.7 D  0.3E x  1.0 E y
8 0.7 D  0.3E x  1.0 E y
Where E x  M x due to Earthquake in Y
E y  M y due to Earthquake in X
D  PSELF W T  PGRAVITY
Moment sign convention
JW Marriott
Lateral System
Greg Kochalski
Reinforcing
Trends:
•Heavy reinforcing in outer areas of flanges
•Light reinforcing in webs
Pier
3
4
5
6
7 outer
7 inner
8 outer
8 inner
Pier Vertical Reinforcing Schedule
Spacing
As
ρ, per Pier ρ, per section
Rebar #
Rows
(in)
(sq. in.)
(%)
(%)
9
1
16
18
0.26
0.94
9
2
6
38
1.41
9
2
6
38
1.41
9
1
11
15
0.40
3.5
9
3
30
1.13
1.16
9
2
6.5
24
1.70
9
3
30
1.13
3.5
9
2
6.5
24
1.70
Pier
3
4
5
6
7
8
Pier Horizontal Reinforcing Schedule
Spacing
ρ, per Pier
Rebar #
Rows
As (in2/ft)
(in)
(%)
4
2
10
0.48
0.25
5
2
10
0.74
0.26
5
2
10
0.74
0.26
4
2
10
0.48
0.25
5
2
0.74
0.26
10
5
2
10
0.74
0.26
Lateral System
Verifying the Results
JW Marriott
Greg Kochalski
JW Marriott
OUTLINE
Greg Kochalski
Introduction
Existing Structure
Floor System
Lateral System
Structural Redesign
Floor System
Lateral System
Architectural Redesign
Cost Analysis
Conclusions/Recommendations
Architectural Redesign
JW Marriott
Greg Kochalski
Affected Areas
•Stairwells
•Patron elevators
•First floor service corridor and
restrooms
•Second floor fire corridor
Notable IBC codes
The atrium is a large focal point of the
architecture
1019.1: “exit enclosure shall not be used for other than
egress…”
1019.1.2: “no penetrations shall be allowed except
those related to exit egress or systems directly related
to the function of the exit way…”
Typical Floor
Ground floor
JW Marriott
OUTLINE
Greg Kochalski
Introduction
Existing Structure
Floor System
Lateral System
Structural Redesign
Floor System
Lateral System
Architectural Redesign
Cost Analysis
Conclusions/Recommendations
Cost Analysis
JW Marriott
Greg Kochalski
Primary Losses
•PT system more skill intensive
•Lower daily production
•Thicker slab
Secondary Losses
•Duration increase
•Interest earnings
Post tension system require longer
durations and more expensive labor
JW Marriott
Cost Analysis
Greg Kochalski
Direct Loss Comparison
Flat Plate
Location
Grand Rapids
Crew
C-17B
Daily Output (cy)
30.24
Labor Hours (cy)
6.878
Material ($)
242
Labor ($)
253
Equipment ($)
24
Total ($)
519
Post Tension (x2.0)
Location
Monterey
Crew
(2) C-17B
Daily Output (cy)
20
Labor Hours (cy)
8.2
Material ($)
475
Labor ($)
630
Equipment ($)
31
Total ($)
1136
Post Tension (x3.0)
Location
Monterey
Crew
(3) C-17B
Daily Output (cy)
30
Labor Hours (cy)
8.2
Material ($)
475
Labor ($)
945
Equipment ($)
31
Total ($)
1451
Concrete (cy)
Material ($)
Labor ($)
Equipment ($)
Total ($)
Incl. O&P ($)
Duration (weeks)
Concrete (cy)
Material ($)
Labor ($)
Equipment ($)
Total ($)
Incl. O&P ($)
Duration (weeks)
Concrete (cy)
Material ($)
Labor ($)
Equipment ($)
Total ($)
Incl. O&P ($)
Duration (weeks)
5707
1,381,094
1,443,871
136,968
2,961,933
3,909,752
38
7228
3,433,300
4,553,640
224,068
8,211,008
10,427,980
72
*Actual duration of 47 weeks
due to weather
Secondary Losses
•$230/night average room price
•60% occupancy expected
•$8 million lost in 25 week delay
7228
3,433,300
6,830,460
224,068
10,487,828
13,319,542
48
JW Marriott
OUTLINE
Greg Kochalski
Introduction
Existing Structure
Floor System
Lateral System
Structural Redesign
Floor System
Lateral System
Architectural Redesign
Cost Analysis
Conclusions/Recommendations
Conclusions and
Recommendations
JW Marriott
Greg Kochalski
Non-linear response
•Plastic hinging mechanism in beams
•Shear walls well below yield, system deforms
evenly
Floor System
•Post Tension system viable alternative
•Costs of PT are staggering, use original flat plate
system
Architecture
•Atrium remains focal point
•Original spaces accounted for
JW Marriott
Greg Kochalski
Acknowledgements
Bert Crandell
Ben Kochalski
Pete Jackson
Jeff Styles
Erika Johnson
Dr. Boothby
Dr. Lepage
All AE Faculty
Mom and Dad
My Friends
And Everyone Else that Made
Thesis a Reality
Questions?