既有地下室外墙影响下的挡土结构非极限主动土压力

中文摘要: 针对挡土结构土压力与位移之间的关系，提出一种适用于既有地下室外墙影响下的挡土结构非极限主动土压力计算方法。基于卸荷路径推导了土体力学参数与位移关系和考虑土拱效应下的非极限主动土压力系数，运用应力状态法和静力平衡法给出了既有地下室外墙影响下的非极限主动土压力统一解，通过与室内相关模拟试验对比，采用应力状态法得到的结果较静力平衡法更接近于实际。基于挡土结构非极限主动土压力变化规律，讨论了位移比、两墙间距、墙土摩擦角、黏聚力等参数对土压力分布、合力及倾覆力矩的影响，揭示了其变化规律。通过与物理实验和算例与理论计算方法所得土压力和力矩的对比表明，所建立的计算方法合理可行，为进一步研究挡土结构非极限主动土压力理论计算提供了一定的依据。
Abstract:For research the relationship between pressure and displacement of retaining structure, a method for calculating the non-limited active earth pressure of retaining structures under the influence of the external wall of basement was proposed. Based on the unloading path, the mechanical parameters of soil and the displacement relationship and the non-limited active earth pressure coefficient were deduced. Then, the stress state method and the forces equilibrium method were used to solve the non- limited active earth pressure, and by comparing indoor physics experiments, the results of the stress state law were relatively closer to reality than forces equilibrium method. Based on the variation of active earth pressure of retaining structure, the influence of displacement ratio, two walls pacing, wall friction angle and cohesive force on earth pressure distribution, resultant force and overturning moment were discussed. The comparison between the results of the physical experiments and numerical examples and theoretical calculation method of the soil pressure and torque showed that the calculation method is reasonable and feasible, which provides a basis for further study of the non-limited active earth pressure theory.