000018450 001__ 18450
000018450 005__ 20170118182223.0
000018450 04107 $$aeng
000018450 046__ $$k2017-01-09
000018450 100__ $$aMatsuda, Hiroshi
000018450 24500 $$aEffects of Cyclic Shear Direction on Earthquake-Induced Pore Water Pressure and Settlement of Clay Layer

000018450 24630 $$n16.$$pProceedings of the 16th World Conference on Earthquake Engineering
000018450 260__ $$b
000018450 506__ $$arestricted
000018450 520__ $$2eng$$aIn this paper, normally consolidated specimens of Kaolinite clay, Tokyo bay clay and Kitakyushu clay were tested under undrained uni-directional and multi-directional cyclic simple shear. The effect of cyclic shear direction on the pore water pressure accumulation during undrained cyclic shear and on the settlement after cyclic shear were investigated by focusing on the normalized pore water pressure ratio (DU) and post-cyclic settlement in strain (Dε), which are defined as the ratio of those induced by multi-directional cyclic shear ((U dyn /σ’ v0 ) M and ε M ) to those induced by uni-directional one ((U dyn /σ’ v0 ) U and ε U ), and also focusing on the difference of pore water pressure ratio (∆U) and post-cyclic settlement (∆ε), which are defined as the difference between (U dyn /σ’ v0 ) M , ε M and (U dyn /σ’ v0 ) U , ε U , respectively. It is shown from the experimental results that for all specimens, DU and Dε firstly reach their peaks (DU max and Dε max ) at the shear strain amplitude of about γ DUmax = 0.1% - 0.4% for U dyn /σ’ v0 and γ Dεmax = 0.1% - 0.2% for ε, then decreasing to smaller values. For clays used in this study, plasticity index is in the range from I p = 25.5 to 63.8, then the maximum normalized pore water pressure ratio increases from DU max = 2.19 to 3.12, which is smaller than the maximum normalized post-cyclic settlement being from Dε max = 2.62 to 3.62. As to the difference of pore water pressure ratio and post-cyclic settlement, ∆U and ∆ε firstly increase with the shear strain amplitude up to their maximum value (∆U max and ∆ε max ) and decrease. For the range of I p from 25.5 to 63.8, ∆U max decreases from 0.34 to 0.20, being smaller than ∆ε max which also falls from 2.56% to 1.02%, respectively. Meanwhile the shear strain amplitude for these peak values increases from γ ∆Umax = 0.3% to 1.2% and from γ ∆εmax = 1.0% to 1.2%. Therefore, it is suggested that the higher the Atterberg’s limit (plasticity index) of clay, the smaller the effect of cyclic shear direction on the pore water pressure and the settlement becomes.

000018450 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000018450 653__ $$aclay, cyclic simple shear, pore water pressure, settlement, undrained

000018450 7112_ $$a16th World Conference on Earthquake Engineering$$cSantiago (CL)$$d2017-01-09 / 2017-01-13$$gWCEE16
000018450 720__ $$aMatsuda, Hiroshi$$iNhan, Tran Thanh$$iSato, Hidemasa
000018450 8560_ $$ffischerc@itam.cas.cz
000018450 8564_ $$s487675$$uhttps://invenio.itam.cas.cz/record/18450/files/1483.pdf$$yOriginal version of the author's contribution as presented on USB, paper 1483.
000018450 962__ $$r16048
000018450 980__ $$aPAPER