考虑颗粒破碎效应的堆石料静动力本构模型

为合理反映颗粒破碎对堆石料力学特性的影响，基于试验结果分析，得出了堆石料在压缩和剪切作用下的颗粒破碎特性规律。通过引入压缩破碎和剪切破碎的相关参数，借鉴已有本构模型的合理定义，吸收临界状态理论和边界面理论的优点，发展了考虑颗粒破碎和状态相关的堆石料静动力统一弹塑性本构模型，并阐述了模型参数的确定方法。该模型不仅能够反映堆石料在静力荷载作用下的低压剪胀、高压剪缩、应变软化和硬化等特性，还能够反映在循环荷载作用下应力-应变的滞回特性和残余变形的累积效应。最后为验证模型的合理性，分别对堆石料的静力三轴和循环三轴试验进行了数值模拟预测，结果表明：模型预测与试验数据吻合良好，所提出的本构模型能够合理地描述颗粒破碎对堆石料静动力变形特性的影响。

A static and dynamic constitutive model of rockfill material considering particle breakage

In order to reasonably reflect the influence of particle breakage on the mechanical properties of the rockfill material, it is obtained by the analysis of the test results that the particle breakage characteristics of the rockfill material under the compression and shear. By introducing the related parameters in the compression breakage and shear breakage, some reasonable definitions of the existing constitutive models are used. Taking the advantages on the critical state theory and the boundary surface theory, a unified constitutive model is developed considering the particle breakage and state parameter, and the determination method of model parameters is described. The model can reflect not only the low pressure dilatancy, high pressure shear shrinkage, strain softening and hardening phenomenon of the rockfill material under the static loading, but also the stress-strain hysteresis characteristics and the cumulative effect of residual deformation under the cyclic loading. Finally, in order to verify the reasonability of the model, the static triaxial and cyclic triaxial tests of rockfill material are carried out. The results show that the model prediction is in good agreement with the experimental data, and the constitutive model can reasonably describe the impact of particle breakage on the static and dynamic deformation characteristics of the rockfill material.