结构性软黏土时效特性的一维弹黏塑性模拟

为了研究土体结构破坏对软黏土一维变形的时效特性的影响，在Bjerrum的等时间线体系基础上，提出了等黏塑性应变率线等黏塑性应变率线概念，建立了非结构性软黏土的一维弹黏塑性模型；为了描述土体结构渐进破坏特征，定义了结构性参数--结构应变，在非结构性模型的基础上推导了结构性软黏土一维弹黏塑性模型；讨论了通过试验法直接确定模型参数的方法，并利用新建模型对温州天然软黏土的一维常规压缩试验、天然Ariake 黏土的分级快速固结试验、结构性Berthierville黏土的一维等应变率压缩试验及长期蠕变试验进行模拟。模拟与试验结果的对比表明，该模型能较好地描述结构性软黏土一维压缩变形的时效特征。

One-dimensional elastic visco-plastic modelling of time-dependent behavior of structured soft clays

To explore the effect of structural damage on the time-dependent behavior of structural soils, a one-dimensional elastic visco-plastic (1DEVP) constitutive model is developed with introducing a new concept of constant visco-plastic strain rate lines, based on Bjerrum’s time lines. To describe the progressive destruction, a new structural parameter named “structural strain” is defined and a new mathematical formula is proposed based on characteristics of soil structure degradation under the one-dimensional loading condition. The method for calibrating the proposed model is discussed, and the proposed model is used to simulate conventional compression tests on Wenzhou natural clays, step loading fast-consolidation tests on natural Ariake clays, constant rates of strain tests (CRS) oedometer tests and long-term creep oedometer tests on structured Berthierville clays. The comparisons between simulations and experimental results show that the newly proposed 1DEVP model can reasonably describe destructuration effects on the time-dependent behavior of structured soft clays.