基于弹黏塑性本构模型的旋转硬化规律

 为更好地反映原状K0固结软土的变形特性，在已建立的考虑软土初始诱发各向异性的弹黏塑性模型基础上，进一步研究软土的旋转硬化规律。通过分析土体在等向固结过程中的黏塑性体积变化，推导表征黏土各向异性演化速率的旋转硬化参数b的理论表达式，便于实际应用。针对浙江温州原状软黏土进行三轴不排水压缩和拉伸剪切试验，分析K0固结温州软黏土的应变率效应以及旋转硬化规律对其受力变形性状的影响。对比分析试验结果与模型计算结果，验证模型及旋转硬化规律的有效性和适用性。

ROTATIONAL HARDENING LAW BASED ON ELASTOVISCOPLASTIC CONSTITUTIVE MODEL

Based on the proposed anisotropic elastoviscoplastic constitutive model for K_0-consolidated clays,a suitable rotational hardening law accounting for changes in anisotropy due to viscoplastic strains is adopted. The expression of the rotation parameter b is presented by analyzing the soil's volumetric changes during isotropic loading. Series of triaxial undrained compression and extension tests have been carried out on the natural K_0-consolidated Wenzhou soft clay. Followed by comparison between the predicted results and the experimental data,the proposed model with rotational hardening law is capable of capturing key features of viscoplastic behaviors of soft soil,and the importance and applicability of rotational hardening law is indicated and verified.