Excess Pore Water Pressure and Settlement of Saturated Clay Induced by Multi-Directional Cyclic Shear

Hiroshi MATSUDA

IGC D6 D7

1) NS EW

2)

Pyke 3)

4)

4)

5)-9)

N-S E-W1)

1)

－ 1 －

招待論文公益社団法人地盤工学会中国支部論文報告集

地盤と建設　Vol. 31, No. 1, 2013

Kjellman 70mm

20mm

75.4mm 2mm

15-16

2 2

0.05

4

( s = 2.707

g/cm3 wL=47.8% wP=22.3%

IP=25.5 Cc=0.305)

80

49kPa 98kPa

3t

49kPa

1.11 1.19 98kPa 1.05 1.08

B 0.95

n

2

2 X Y

2

=0.05% 3.0%

10 20 50 100 200

2

X

Y 0.05

X Y x y

X Y x y

(= x= y)=1.0%

20° 45 70 90

X

x 1.0%

x= y= =1.0% X Y

X Y

=20 45 70 90

－ 2 －

松田

=90

gyratory shear

3

3.1

Udyn

Udyn/ n

=0.1% 0.4% 2.0%

Udyn/

5)

n

0

0

0

0

(1)

(2)

(3)

2 3 A B C m

1

10)

X Y10)

10)

(2) (3) 10)

10 6.0 -0.090 1.010 -1.820 6.0 -0.089 1.014 -2.050 6.0 -0.085 1.023 -2.2100 6.0 -0.080 1.027 -2.4200 7.0 -0.080 1.030 -2.510 2.2 -0.068 0.998 -2.220 2.2 -0.065 1.002 -2.250 2.3 -0.058 1.009 -2.2100 2.5 -0.050 1.012 -2.2200 3.9 -0.050 1.018 -2.2

(2) (3) 10)

－ 3 －

多方向繰返しせん断を受けた飽和粘土の過剰間隙水圧および沈下に関する研究

2 3 A

B C m

=45 =90

=90

98kPa

1

n=10 200

1

=20 45 70 90

(a)

(b) =45

(c) =90

10) =49kPa

10) =98kPa

10)(n=10)

0

0.2

0.4

0.6

0.8

1

0.01 0.1 1 10

n = 10

( 'v0=98kPa)

( 'v0=49kPa)''''''''U

dyn/

’ vo

=90°

=70°

=45°

=20°

=90°

(%)

－ 4 －

松田

98kPa 49kPa

1

=9011)

1

1

n<50 1

n>50

1

1 n<50

1

1995 1

17

12) 1

2 1

2

2

5)

10)(n=200)

0

0.2

0.4

0.6

0.8

1

0.01 0.1 1 10

Exce

ss p

ore

wat

er p

ress

ure

ratio

Udy

n/' vo

Shear strain amplitude (%)

Kaolinn = 200

= 900 ( 'v0=98kPa)

= 900 ( 'v0=49kPa)= 700 '' = 450 '' = 200 ''

uni ''

Calculated (uni)Calculated (multi)

Udy

n/’ v

o

(%)

=90=70=45=20

=90

-10)

0

0.2

0.4

0.6

0.8

1

0.01 0.1 1 10

Exce

ss p

ore

wat

er p

ress

ure

ratio

Udy

n/' vo

Shear strain amplitude (%)

n = 200n = 100n = 50n = 20n = 10

Kaolin'v0 = 49kPa

Uni-direction

Calculated (uni)

(%)

Udy

n/’ v

o

10) =90

0

0.2

0.4

0.6

0.8

1

0.01 0.1 1 10

Exce

ss p

ore

wat

er p

ress

ure

ratio

Udy

n/' vo

Shear strain amplitude (%)

n = 200n = 100n = 50n = 20n = 10Calculated (multi)

Kaolin'v0 = 49kPa= 900

Udy

n/’ v

o

(%)

=90

199512)

－ 5 －

多方向繰返しせん断を受けた飽和粘土の過剰間隙水圧および沈下に関する研究

Cdyn

(4)

e0 e H0

H 4 SRR

(Stress Reduction Ratio)

SRR 5

4

e SRR

n=10 n=200

CdynU CdynM

17

CdynU CdynM

CdynU= 0.060

n=10 CdynM=0.064 n=200

CdynM=0.075

18 19 18

n=10 19 n=200

(5)

10) n=10

SRR

0.00

0.05

0.10

0.15

0.20

1 10 100

e

Stress reduction ratio

e = CdynU.log(1/(1-Udyn/ 'v0))

Kaolin; 'v0 = 49kPa= 0.05%-3.0%

n = 10

= 900

= 700

= 450

= 200

uniCalculated (multi)

e = CdynM.log(1/(1-(Udyn/ 'v0))

Calculated (uni)

e

SRR

=90

=70

=45

=20

e=CdynM log(SRR)

e=CdynU log(SRR)

SRR

0.00

0.05

0.10

0.15

0.20

1 10 100

e

SRR

e = CdynU.log(SRR)

e = CdynM.log(SRR)

= 900

= 700

= 450

= 200

uni

Kaolin; 'v0 = 49kPa= 0.1%-2.0%; n = 200

Calculated (uni)Calculated (multi)

e

SRR

=90=70

=45

=20

e=CdynM log(SRR)

e=CdynU log(SRR)

10)

0.05

0.06

0.07

0.08

0 50 100 150 200Number of cycles n

Multi-directionUni-directionC

yclic

reco

mpr

essio

n in

dex

Cdy

n Kaolin'v0 = 49kPa

, CdynU = 0.060, CdynM = 6 x 10-5 n + 0.065

n

Cdy

nUC

dynM

’vo=49kPa

－ 6 －

松田

G*

13)

G*

G*

6

7

X YG* X

Y 20

G*

G*

8

9

n=50

10) n=200

G*13)

G*14)

0

500

1000

1500

2000

2500

3000

0.0 1.0 2.0 3.0

Cum

ulat

ive s

hear

stra

in G

* (%

)

Shear strain amplitude (%)

Kaolin'v0 = 49kPa

Multi-direction n = 200

= 900

= 700

= 450

= 200

n = 100

n = 50

n = 20 n = 10

G* = n (5.995 + 0.3510)

=90

=70

=45

=20

(%)

G*

(%)

G*14)

0

500

1000

1500

2000

2500

3000

0.0 1.0 2.0 3.0

Cum

ulat

ive s

hear

stra

in G

* (%

)

Shear strain amplitude (%)

Kaolin'v0 = 49kPa

Uni-direction

G* = n (3.950 + 0.0523)

n = 200

n = 100

n = 50n = 20 n = 10

(%)

G*

(%)

－ 7 －

多方向繰返しせん断を受けた飽和粘土の過剰間隙水圧および沈下に関する研究

=0.4%

4)

10

10 Udyn=

11

10 11 2 3

A B C m

A B C m

11

n=10 50 200

11 SRR G*

(11)14)

14)14)

－ 8 －

松田

SRR 12

12 4

G*

G*

4

NS EW

2

maxNS=0.57% maxEW=0.34%maxNS=1.15% maxEW=0.68% maxNS=2.30%

maxEW=1.51%

dyn

NcyMalhotra15)

EW4.7 NS 4.2 14)

16)

13

F G

14

15

H I

14)

13

EW NS

EW NS

dyn

14)

14)

－ 9 －

多方向繰返しせん断を受けた飽和粘土の過剰間隙水圧および沈下に関する研究

11

16

D 16

14)

NS

NS

2

49kPa 98kPa

G*

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14)

14)

－ 10 －

松田

saturated clay layer induced by cyclic shear, Soils and Foundations, Vol.28, No.3, pp.103-113, 1988.

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PP.59-64, 1998. 12)

,No.659/III-52, pp.63-75, 2000

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/III 12, 143 151, 1989. 14) Matsuda H., Tran Thanh Nhan, and Ishikura R.: Prediction

of excess pore water pressure and post-cyclic settlement on soft clay induced by uni-directional and multi-directional cyclic shears as a function of strain path parameters, Soil Dynamics and Earthquake Engineering, 49, pp.75–88, 2013.

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(2013 11 17 )

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多方向繰返しせん断を受けた飽和粘土の過剰間隙水圧および沈下に関する研究