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(a) (b) 1) 15-1 1) LIQCAOka 199Oka 1999 ),3) ) -1-39 -
1) a) b) i) 1) 1 FEM Zhang ) 1 1) - 35 -
FEM 9 1 3 ii) () 1 Dr=9% Dr=35% Tatsuoka 19Fukushima and Tatsuoka19 5),) Dr=35% Dr=35% Dr=3%1kPa 1kPa - 351 -
1 ρ (t/m 3 ) 1.3 1.. k (m/s) 1.1 1-1. 1-1. 1 - e 1.19.. V s (m/s) 7 7 13 R L1.15.3. λ.5.3.3 κ.9.. OCR 1. 1. 1.5 G /σ' m 753 53 33 M f 1.9 1.15 1. M m 1.7.99.99 B 15 15 B 1 1 3 1 γ p r..3.1 γ e r..5.3 D. 1..5 n.. 5. Dr=35% -1 Creager Dr=9% 1.5 1 - -1 Dr=35%(a) (b)(c)(d) 3% 1kPa.15..3.1. 1. 1-35 -
.3. 5 Shear strain.1. -.1 Shear stress (kpa) 3 1 -. -1 Shear stress (kpa) -.3 5 3 1-1 5 1 step 15 (a) - -.3 -. -.1..1..3 Shear strain (b) Shear stress (kpa) 5 3 1-1 - - 5 1 15 Effective mean stress (kpa) (c) (d) 3 Dr=35% step.5. Model Experiment 1.. Toyoura Dr=3%.3.5 Shear stress ratio.3. G/G....15.1 Damping factor.1 Toyoura Dr=3% DA=7.5%..5. 1 3 5 7 1 3 5 7 1.. 1-1 -5 1-1 -3 1 - Number of cycles (a) Shear strain amplitude (b) 1.5 1. Toyoura Dr=3% R=.15 1.5 1. shear stress (kpa).5. -.5 shear stress (kpa).5. -.5-1. -1. Toyoura Dr=3% R=.15-1.5-3x1-3 -1.5 1 shear strain effective mean stress (kpa) (c) (d) Dr=35%.3 Dr=35% (a)(b) - 353 -
.1 1 Shear strain.5. -.5 Shear stress (kpa) 5-5 -.1 1 3 x1 3 1 step (a) -1 -.1 -.5..5.1 Shear strain (b)..5 Shear stress (kpa) 5-5 Volumetric strain..3..1-1. 9. 9.5 1. 1.5 1 3 x1 3 Effective mean stress (kpa) (c) (d) 5 step (c)(d) 1 Tatsuoka 19 5) (c) 5 (a) (b)(c)(d) 1.35g/cm 3 1kPa.13.3.53.13.3.53.13 (d) 1.1 () 1GPa 7.5t/m 3 5.mm 1.5mm mm - 35 -
iii) FEM 1 1 1cm5cm 1 (a)(b) 5mm.5mm - 355 -
(a) (b) 1 (a) (b) 7 1 (a)(b) 7 1 1 1.mm 5Gal 5Hz.15 Newmark =.35=. Rayleigh 1.9 3%.9.5-35 -
c) 3 1 1 3 3 d) 1 i) Dr=35% 9 W-1 W3- W-1 W1- W-.5 1 1 Dr=35% 1 Dr=35% 1 ii) 1 Dr=35% Dr=35% - 357 -
W-1 W1- E.P.W.P (kpa) E.P.W.P (kpa) E.P.W.P (kpa) 1 1 Time (s) Time (s) (a) W-1 (b) W1- Time (s) W- E.P.W.P (kpa) 1 1 Time (s) (a) W- (b) W3-1 W3-9 1 1 11 (a) (b) 13 (c) 9 DY-NL(d) 13 1/ 1/ - 35 -
Y-Acceleration (m/s/s) - - Input motion Y-Acceleration (m/s/s) 1 5-5 -1 Top of pile- X-Displacmement (m) Time (s) (a). -.1 -. -.3 Top of sheet pile Time (s) (b) X-Displacmement (m) - - - -x1-3 Top of pile- Time (s) Time (s) (c) (d) 11 1 iii).5 1 13 1 No.1No.3 No. No. No.1No.3 No.No. Dr=35%.5m1.m Dr=35% 11 1 e) 3 i) 3-359 -
1. 1. No. 1. 1. No.5 1. 1. No. 1. 1. 1. Height (m) 1.. Height (m) 1.. Height (m) 1......... -.5.. -.5.. -.5. Moment (knm) Moment (knm) Moment (knm) (a) (b) (c) 1. 1. No.1 1. 1. No. 1. 1. No.3 1. 1. 1. Height (m) 1.. Height (m) 1.. Height (m) 1......... -.5.. -.5.. -.5. Moment (knm) Moment (knm) Moment (knm) (d) (e) (f) 1 1 13 1 (a) 9 DY-NL (b) 13-3 -
X-Displacmement (m). -.1 -. -.3 Top of sheet pile 3 X-Displacmement (m) - - - -x1-3 3 Top of pile- Time (s) Time (s) (a) (b) 1 3 (a) (b) 3 15 H=1.m 3 (a) (b) 3 1 H=1.m 3 1 1 5% 1 1.5-31 -
3 15 1 15 1.m 1 Dr=35% 1.m 15 3 1 Dr=35% 1.m 15 3 1 15 ii) 3.5 17 13 13 3 1 3 3 1. 1. No.1 3 1. 1. No. 3 1. 1. No.3 3 1. 1. 1. Height (m) 1.. Height (m) 1.. Height (m) 1......... -.5.. -.5.. -.5. Moment (knm) Moment (knm) Moment (knm) (a) (b) (c) 17 3-3 -
) Hashiguchi, 199: Hashiguchi and Chen, 199 7),) Masing Sekiguchi and Ohta (1977) 9) Hashiguchi and Tsutsumi, 1 1) 1)1 1 i) 3 Layers 1-3 Layer Dr=5%9 Layers 1 & 3 Layer 1 (dry) P-1 P- Layer (saturated) Total mesh number: 1 Mesh size: 11m P-3 Sine wave: 5Hz, 5Gal Layer 3 (saturated) Input (sine wave) 1 Shear stress ratio.5..3..1 Toyoura Dr = 5 % DA =7.5 % Model Experiment 1 1 1 Number of cycle 19-33 -
3 1. ν ( G). ρ 3. γ. p i 5. φ ( m). u 7. c. µ 9. φ ( m ) 1. b r 11. φ ( m ) 1. σ d b d b 13. 1. s F 15. β ν =.33 ρ =.5 γ =.1 Layer Layers 1 & 3 F = f u = φ = c = 1 φ d = 33 µ =. ν =.33 ρ =.5 γ =.1 F = 1 f u = φ = 1 c = φ d = µ = f = p (1+ )φ - 3 -
Shear stress (kpa) 15 1 5-5 -1-15 - P-1 P- P-3 5 1 15 Effective mean stress (kpa) Shear stress (kpa) 15 1 5-5 -1-15 - P-1 P- P-3 -. -. -.... Shear strain 1-35 -
1) 1/1/ ) (e) 1).3.. ) Oka, F., Yashima, A., Shibata, T., Kato, M. and Uzuoka, R.: FEM-FDM coupled liquefaction analysis of a porous soil using an elasto-plastic model, Applied Scientific Research, Vol.5, pp.9-5, 199. 3) Oka, F., Yashima, A., Tateishi, A., Taguchi, Y. and Yamashita, S.: A cyclic elasto-plastic constitutive model for sand considering a plastic-strain dependence of the shear modulus, Geotechnique, pp.1-, 1999. ) Zhang, F., Kimura, M., Nakai, T. and Hoshikawa, T.: Mechanical behavior of pile foundations subjected to cyclic lateral loading up to the ultimate state, Soils and Foundations, Vol., No.5, pp.1-17,. 5) Tatsuoka, F., Muramatsu, M. and Sasaki, T.: Cyclic undrained stress-strain - 3 -
behavior of dense sands by tosional simple shear test, Soils and Foundations, Vol., No., pp.55-7, 19. ) Fukushima, S. and Tatsuoka, F.: Strength and deformation characteristics of saturated sand at extremely low pressures, Soils and Foundations, Vol., No., pp.3-, 19. 7) Hashiguchi, K.: Subloading surface model in unconventional plasticity, Int. J. Solids Struct., 5(), 917-95, 199. ) Hashiguchi, K. and Chen, Z. P.: Elastoplastic constitutive equation of soils with the subloading surface and the rotational hardening, Int. J. Numer. Anal. Meth. Geomech.,, 199-7, 199. 9) Sekiguchi, O. and Ohta, H.: Induced anisotropy and time dependency in clays, Constitutive Equations of Soils (Proc. 9th Int. Conf. Soil Mech. Found. Eng., Spec. Session 9), Tokyo, JSSMFE, pp. 9-3, 1977. 1) Hashiguchi, K. and Tsutsumi, S.: Elastoplastic constitutive equation with tangential stress rate effect. Int. J. Plasticity, Vol. 17(1), pp. 117-15, 1. (f) Prediction of Earth Pressures on a Pile Group Due to Liquefaction-induced Ground Flow Sixth World Congress on Computational Mechanics (WCCM VI) in conjunction with the Second Asian-Pacific Congress on Computational Mechanics (APCOM') (g) ) 3) - 37 -
(3) (a) - (b) 1 1 E - 3 -