饱和土体固结压缩和蠕变的热力学本构理论及模型分析

Thermodynamic constitutive theory and analysis of consolidation compression and creep of saturated soils

岩土热力学模型(thermodynamic soil model,TSM)是基于颗粒固体的非平衡态热力学理论,建立的一种崭新的描述岩土力学问题的统一理论模型。该模型引入"颗粒熵运动"和"弹性弛豫",对土体颗粒层次的耗散机制进行了合理地考虑,这些使得模型能够更深入描述土体的变形和能量耗散机理,从而能够在统一理论框架中描述岩土体复杂多变的物理力学行为。基于该理论模型,研究了饱和土体的固结压缩和蠕变问题,分析了加载速率、应力/应变路径和非单调荷载等因素的影响规律。模拟结果表明:模型具有描述复杂条件下的饱和土体的固结压缩和蠕变特性的能力,具有较高的理论和工程应用价值。

The thermodynamic soil model （TSM） is a new unified theoretical model for the analysis ofgeotechnical engineering problems. It is based on the non-equilibrium thermodynamic theory of granular solids. The granular entropy and the elastic relaxation are introduced for describing the energy dissipation mechanism on particle level, which allows the model to simulate the various physical properties of the soils, including the overall deformation and the energy dissipation. Based on the TSM, the influence of strain rates, stress/strain paths and non-monotonic loads on the consolidation and creep behaviors of saturated soils are studied in the paper. The results show that the theoretical model is able to describe the consolidation and creep of saturated soils under complex conditions, and it is of high theoretical reference value for geotechnical engineering field.