【摘要】 微分层平衡是近50年国内外挡土墙土压力曲线分布计算理论研究方法的基础,其侧土压力系数假定方法虽然各不相同但随墙面摩擦角变化规律都与库仑土压力系数悖逆却是共性,推导过程假设计算的侧土压力系数与结论合力土压力系数是仅有定义概念差别的同一物理量却自相矛盾。根据微分层平衡所得土压力分布计算公式数学原理,揭示了只要采用此方法得出土压力为曲线分布的研究成果,必然是假设与结论侧土压力系数自相矛盾并悖逆经典理论的谬论。依该文提出的非极限状态土压力研究方法,有限元模拟计算揭示的变形应力成果,表明挡土墙实际的土压力分布曲线特别是墙底段和铅直土压力根本不同于微分层理论计算结果,进一步阐明了微分层平衡模型不能用于考虑墙面摩擦的挡土墙土压力曲线分布研究,否则假设与结论的自相矛盾、墙底段土压力分布的严重失真而成为谬论,是微分层平衡数学原理和力学模型简化的内在本质必然。更多还原

【Abstract】 In the past 50 years,differential stratum equilibrium has been the basis of calculation theory research of earth pressure against retaining walls at home and abroad,but a common problem is that the change law of the lateral earth pressure coefficient with the friction angle between wall back and soil was contrary to the coulomb’s resultant force,that is,the assumptions on coefficient of lateral earth pressure are different,the assumed coefficient of lateral earth pressure and coefficient of resultant force of lateral earth pressure are actually the same physical variable and they differ only in the definition and concept,but they are contrary to each other. Based on the mathematical principle for lateral earth pressure distribution formula derived from differential stratum,it is disclosed that the achievement obtained from differential stratum that the curved distribution of earth pressure shall be the necessary result due to the self-contradiction in assumption and result of lateral earth pressure coefficients,leading to a mistake which is contrary to classical theoretic law. Based on the research method for non-limit state earth pressure and the deformation and stress results from FEM simulation,it is shown that the real distribution curve of earth pressure against retaining walls is remarkably different from the calculating result by using differential stratum method,especially at the bottom of wall and the vertical part.Furthermore,it is clarified that the differential stratum equilibrium method can not be used for studying the distribution curve of earth pressure against retaining walls when considering the frictional force behind wall,otherwise,the mistake may occur due to the self-contradiction in assumption and conclusion and the severe deviation of earth pressure at the part close to the bottom of wall,which shall be attributed to the difference between mathematical principle of differential stratum equilibrium and simplification of mechanical model.更多还原