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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Study on Dynamic Behavior ofWooden Horizontal Hybrid Structure
Involving Stiff Cores
Yoshihiro YAMAZAKI (Assist. Prof., Tokyo Institute of Technology, Japan)
Hiroyasu SAKATA (Prof., Tokyo Institute of Technology, Japan)
16th U.S.-JAPAN-N.Z. WORKSHOP ON IMPROVEMENT OFSTRUCTURAL ENGINEERING AND RESILIENCYJune 27-29, 2016, Todaiji Temple Cultural Center, Nara, Japan
Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
1. Background
Vertical hybrid structure Horizontal hybrid structure
RC
Wood
RCWood
RCWood
WoodDesign hand book
Horizontal hybrid structure
RCWood
RCWood
WoodHorizontal hybrid structure
RCWood
RCWood
WoodVertical hybrid structure
RC
Wood
Vertical hybrid structure
RC
Wood
• Wood structures have been built mainly as small detached houses so far. But large buildings are also expected to be built by wood because of environmental issue.
• Hybrid structure has advantages to enhance the seismic resistance.
• Design handbook for wood hybrid structures were published. However, horizontal hybrid structures are NOTcovered.
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
2. A Prototype of Horizontal Hybrid Structure of Wood and RC
1680
00
8000 8000 8000 8000 8000 80008000 8000 80008000 8000 80008000 8000 2400024000 48000
112000
8000
8000
Wood Core(RC)
Wood Core(RC)
Wood
X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 X11 X12 X13 X14 X15
Y1
Y2
Y3
Architectural Institute of Japan (2012), “Technical Issues and resolutions of Large Wood Building” (in Japanese), Material of AIJ annual meeting 2012
3-story school buildingFloor area=5,532m2
Height=13.4m
Wood : Glued-laminated timber's framing and plywood sheathing walls and floor diaphragms
RC core : RC frame with shear walls
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Wood part dominant 1st mode Wood part dominant 2nd mode
Core part dominant 1st mode Core part dominant 2nd mode
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
3. Characteristics of Seismic Response Connectionforce
Connectionforce
Wood Core
Force distributionForce distribution
Force transmission
Force transmission
・ Difference of weight and stiffness between wood parts and RC parts
・ Deformation of floor diaphragm in wood parts
Span dir.
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
4. Objective
The seismic performance of horizontal hybrid structure is demonstrated through shaking table test of scaled specimens.
Then simplified modeling method by two-dimensional continuous model is introduced, and the applicability is discussed.
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Core part(steel jig)
Weights (19kN)
5. Setup of Shaking Table Test
One-sided core
- Wood part
→ One third scaled model
- Core part
→ Steel jigs
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Plywood (t=9mm)Nail (d=2.1mm, L=32mm) @100mm
Plywood (t=12mm)Nail (d=2.1mm, L=32mm) @150mm(No.1,3)/50mm(No.2)
(A) (C)
(B)
Transverse dir. (X1~X3)
910
1213 1213 12131820
Post(60x60mm):Spruce
Beam(60x150mm):Scotch pine
910
910
Longitudinal dir. (Y1, Y2)
(*) Bolts (Φ=6mm)
6. Specimen
Washer24x24mm
(A)
Steel bar 16mm
Base plate with shear ring(Φ27.2, t=2.3)
(B)
(C)Washer24x24mm
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
X4
X3
X2
X1 2
2
2@150mm
Core
2
2
2@50mm
4
0
0@150mm
Core CoreNails’ pitch
The number of walls
No.1No.1 No.2No.2 No.3No.3
7. List of Specimens
Parameters are・ arrangement of shear walls・ nails’ pitch of floor diaphragm (in-plane stiffness)
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Period (sec)
Pse
udo
acc.
(cm
/sec
2 )
Target(5%damping, PGA=0.4g)
Natural period of specimens
8. Input motion Original
Scaled
x 1/√3
Time (sec)
Time (sec)
Acc
.(cm
/sec
2 )A
cc.(
cm/s
ec2 )
Motion PGA
1 WN 0.05g
2 EQ 0.1g
3 WN 0.05g
4 EQ 0.2g
5 WN 0.05g
6 EQ 0.4g
7 WN 0.05g
8 EQ 0.6g
9 WN 0.05g
10 EQ 0.8g
11 WN 0.05g
WN : White NoiseEQ : Artificial Earthquake
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Specimen No.1, PGA=0.8g, Time scale x √3 (original scale)
Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
2
Core
2 2 2 2 2 4 0 0
X3X2X1 CoreX3X2X1 CoreX3X2X1
Flexible diaphragm Stiff diaphragm Flexible diaphragm
9. Maximum Displacement Distribution
No.1No.1 No.2No.2 No.3No.30.4g0.6g0.8g
29.6 20.6 31.8
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Floor diaphragmShear wall
1/120rad
-1/240rad
-1/120rad
1/240rad
No.1No.1
No.2No.2
No.3No.3
No wallNo wall No wallNo wall
10. Force-Deform. Relation of Each Element
PGA0.4g
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1/120rad
-1/240rad-1/120rad
1/240rad
1/60rad 1/60rad 1/60rad1/60rad
PGA0.8g
Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
11. Seismic Force RatioShared by Wood part and Core Part
3F
2F
1F
0 0.5 11
2
3
0 0.5 11
2
3
0 0.5 11
2
3
X1 X2 X3
X1 X2 X3 X1
Wood Core
Floor Floor FloorNo.1No.1 No.2No.2 No.3No.3
Ratio Ratio Ratio
Wood CoreWood Core
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0 0.5 11
2
3
0 0.5 11
2
3
0 0.5 11
2
3X1 X2 X3
X1 X2 X3 X1
PGA0.4gPGA0.4g
PGA0.8gPGA0.8g
Wood CoreWood CoreWood Core
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
x
y
Uniform shear panel(Two-dimensional)
12. Idea of Modeling Method
Uniform shear bar(One-dimensional)
x
Discretizedmodel
(Lumped mass)
Continuousmodel
Useful to obtain
・fundamental period・seismic force distr.
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Core
Ground
Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
2
2
2
2
2
2
y
uG
x
uG
t
uyx
Equation of
wave motion
H
yn
L
xmyx
fmn 2
)12(sin
2
)12(sin,
Get eigen function considering boundary condition
yx
fmn
G
H
nG
L
m22
2
)12(
2
)12(
x
yu(x,y)
y = H
y = 0
x = 0
x = Lf
0),0( yu
0)0,( xu
0),(
x
yLu f
0),(
y
Hxu
13. Equation of Motion
Please seeYoshihiro Yamazaki and Hiroyasu Sakata, 2016, "Simplified Modeling Method and Seismic Force Evaluation of Building Structures Involving Stiff Cores: Study on dynamic behavior of wooden horizontal hybrid structure Part1(in Japanese)", Journal of structural and construction engineering, Architectural Institute of Japan, No.720, pp.291-301
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Pi Qi
N
ijjW
Floor
No.1No.2No.3
A'i (Only 1st mode)A'i (All modes)Ai (Conventional)
Test results Analysis results
Vertical shear coefficient
N
ijjW
Seismic force
Weight abovei-th floor
)2( iAi = Qi / A1
14. Comparison of Vertical Shear Coefficient
)2/sin(
)2/sin(1
23
231
1
11
i
i
ii
i
iA
11/
/
,
11,
NNf
NNfN Wk
WkR 2
2
HG
LG
x
fy
)(5.0
)(5.0
1
1
1
1
1
1
1
NiWRWWRW
NiWRWWRWW
NN
N
jjNN
NN
N
jjNN
N
ijj
i
(Combination of all modes)
(Only the 1st mode)
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
1) 50 to 70% of seismic force acting on wood part was transmitted to core through floor diaphragms. The original intension of horizontal hybrid structure was realized. Therefore not only shear walls but floor diaphragms clearly contribute to seismic force resistance capacity.
2) Applicability of continuous model was discussed. It could improve accuracy of the vertical shear coefficient distribution compared to the conventional formula. The method can be applied to evaluate other dynamic properties.
15. Conclusions18/20
Seismic behavior of wooden horizontal hybrid structure involving stiff cores was discussed.
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Acknowledgment
This work was supported by JSPS KAKENHI Grant Number JP26709039(Grant-in-Aid for Young Scientists (A)) and THE KAJIMA FOUNDATION.
The shaking table test was conducted in Technology Development Division, Fujita corporation.
We would like to express our gratitude to them.
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Tokyo Institute of Technology, Yoshihiro Yamazaki
Study on Dynamic Behavior of Wooden Horizontal Hybrid Structure Involving Stiff Cores
Thank you for your kind attention
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