非饱和原状膨胀土的弹塑性损伤本构模型研究

An elastoplastic damage constitutive model of unsaturated undisturbed expansive soil

以复合体损伤理论为基础,建立了非饱和原状膨胀土的弹塑性损伤本构模型。模型可反映原状膨胀土的三个主要特征(胀缩性、裂隙性和超固结性)造成的独特的力学特性,即,低围压情况下的软化和剪胀,围压较高时的硬化和剪缩以及干湿变化时的反复胀缩特性。模型共包含23个参数,都可由试验测定。

Based on the damage theory of composite substance, an elastoplastic damage constitutive model of unsaturated undisturbed expansive soil was developed. The model can describe the complex mechanical behaviors of undisturbed expansive soil as a result of the three main characters of expansive soil, i.e. high swelling or shrinking deformation, cracks and over consolidation. In detail, the model can reflect the following behaviors of unsaturated undisturbed expansive soil, softening and bulging when sheared under low pressure, while hardening and contracting under high pressure and repeated swelling or shrinking when it was wetted or dried up. There are 23 parameters in the constitutive model which can be determined from the test results of unsaturated undisturbed expansive soil.