【摘要】 简要综述了笔者近30年在砂土动力学5个基本理论方面的主要研究成果:①支配砂土动有效抗剪强度变化的6个基本效应与瞬态有效动强度理论及其细观物理基础;②砂土可逆性与不可逆性剪胀等动本构规律及循环本构理论模型;③砂土震动液化大变形的基本规律、物理机制、本构模型和零应力点算法等本构理论及预测方法;④粗粒土与结构接触面的三维静动力学规律及本构理论模型;⑤考虑刚性挡土结构与地下浅埋结构侧向位移的地震土压力计算理论及实用算法。这些成果是在一系列测试技术研发以及较为深入细致的现象观察、试验模拟、数值仿真、机理探究和理论思考的基础上获得的比较系统的认知与进展。这些研究着眼于理解和描述地震荷载作用等引起的"循环效应",着力于探究和揭示不同条件下砂土的动力学行为及其内在规律,着重于发展和完善"物理概念正确、数学模型简单、参数便于确定、分析简便实用"的计算模型及方法,以期对丰富土动力学基本理论内涵和解决实际土工抗震边值问题能有所裨益。更多还原

【Abstract】 The author’s main achievements in the basic theories of sand dynamics in the past three decades are summarized from the following five aspects:(1) 2D and 3D dynamic effective strength criteria considering six frictional and non-frictional effects;(2) a cyclic elasto-plastic model based on several new experimental findings of constitutive laws such as reversible and irreversible dilatancies;(3) a constitutive theory of large post-liquefaction deformation with emphasis on the establishment of a cohesive theoretical framework consisting of mechanical laws,physical mechanisms,constitutive descriptions,numerical algorithms and pragmatic methods of prediction;(4) a static and cyclic elasto-plastic model for interfaces between soils and structures,which are established based on five basic experimental laws;(5) seismic earth pressure theory for rigid retaining walls and shallow-buried structures under any lateral displacement.These advances are obtained based on experimental observations,numerical simulations,mechanism analysis and theoretical description.Special attention in the present study is paid to the deep understanding of the realistic dynamic behaviours,rational descriptions of the cyclic effects of dynamic loadings induced by earthquakes,and new developments of simplified and pragmatic methods of prediction.更多还原