重塑超固结上海软土力学特性及弹塑性模拟

对典型上海软土重塑样进行了围压不变和平均主应力不变的三轴排水剪切试验，得到重塑上海软土在不同初始超固结比和围压条件下的应力-应变关系，弄清了超固结比、围压以及应力路径对重塑上海软土的变形和强度特性的影响；根据土体的应力-应变曲线得到重塑上海软土的临界状态应力比及内摩擦角。采用姚仰平等建议的基于伏斯列夫面的超固结土本构模型，并根据等向压缩及三轴排水剪切试验确定其模型参数，对保持围压和平均主应力不变的三轴压缩试验进行了模型预测。预测结果表明，此超固结土本构模型能较好地反映重塑超固结上海软土的变形和强度特性。

Mechanical behavior of remolded overconsolidated Shanghai soft clay and its elastoplastic simulation

A number of consolidated-drained triaxial tests were carried out on the remolded Shanghai clay with different over consolidation ratios (OCRs) under constant confining pressures and constant mean principal stresses. The stress -strain relations at different OCRs, confining pressures and stress paths are obtained. The effects of OCR, confining pressure and stress path on the mechanical behaviors of the remolded Shanghai clay are clarified; and the critical state stress ratio and internal frictional angle are obtained. A constitutive model proposed by Yao et al. for overconsolidated clays used to simulate the mechanical behavior of the remolded Shanghai clay with different OCRs using the model parameters from isotropic compression and triaxial shear tests. The simulated results show that the constitutive model can predict well the strength and deformation of the remolded Shanghai soft clay with different OCRs and stress paths.