【摘要】 对于中密砂和密砂,剪胀现象是一个比较显著的特征,相变线是描述剪胀现象的一条特征线,它比较容易确定。因此,以相变线作为状态参考线,提出并定义了一种状态参量,在已有弹塑性模型基础上,将状态参量引入剪胀方程和塑性硬化模量表达式中,建立了一个新的考虑砂土剪胀性的本构模型。该模型尤其适合于中密砂和密砂,对于松砂则退化为原弹塑性模型。模型形式较简单,包含9个材料参数,且比较容易确定。数值模拟结果与试验数据吻合较好。更多还原

【Abstract】 Dense and mudium dense sands dilate under drained conditions and develop negative excess pore water pressure when sheared under undrained conditions. There exists a phase transformation line for dense and medium dense sand which characters the state from contractive to dilative. In the proposed model, the state parameter which makes the phase transformation line as reference line is introduced into the stress-dilatancy equation and the plastic hardening modulus expression to develop a new constitutive model for dilatant sand, 9 model parameters which are convenient to be calibrated are involved. The numerical simulation is in good agreement with the data of triaxial compression tests.更多还原