Evaluation methods for dynamic deformation-strength-crushability properties of volcanic granular soils

在室内试验的基础上，利用SPT、CPT、Dilatometer试验、Seismic Cone试验、PS测井等方法，对火山粗粒地层中未受扰动和受扰动的试样进行了一系列室内试验，获得了循环不排水三轴强度、伪弹性剪切模量、阻尼比、剪切诱导颗粒破碎等力学特性。得到以下结论：(1)利用有效应力比和有效平均主应力可以很容易地估计任意应力路径下固结和剪切引起的颗粒破碎量。(2)在火山土中，应力历史对循环变形-强度行为的影响更为明显，而火山土的颗粒破碎作用明显。(3)揭示了颗粒破碎、胶结作用和沉积环境对测深数据与室内试验计算的变形强度参数相关性的影响。

A series of laboratory tests on the undisturbed and disturbed samples taken from volcanic coarse-grained grounds were carried out to obtain the mechanical properties such as cyclic undrained triaxial strength, pseudo elastic shear modulus, dampimg ratio and shear-induced particle crushing In addition to these laboratory tests, site investigations were also conducted at the naturally deposited volcanic grounds, using SPT, CPT, Dilatometer test, Seismic Cone Test and PS logging. The following conclusions were obtained; (1) Amount of particle breakage induced by consolidation and shearing in arbitrary stress paths can be estimated easily by effective stress ratio and effective mean principal stress. (2) Variation in cyclic deformation-strength behaviors due to stress history was observed more clearly in the volcanic soils with which particle breakage has been significantly induced. (3) Effects of particle breakage, cementation and sedimentary environment on the correlation between the sounding data and deformation-strength parameters evaluated from laboratory tests are revealed.