考虑摩擦损耗的加筋挡土墙临界高度研究

目前加筋挡土墙临界高度研究忽略了土-筋间的摩擦损耗这一客观因素。为进一步完善加筋挡土墙临界高度计算公式，基于极限分析上限法，充分考虑加筋挡土墙发生内部破坏时，速度间断面上筋材和土体的能量损耗率以及两者之间的摩擦损耗率，建立分析方程并推导出加筋挡土墙临界高度计算公式，然后采用离心试验数据应用该文推导公式进行求解验算。结果表明：将摩擦损耗计入内部能量损耗求得的加筋挡土墙临界高度更加接近离心试验结果与筋材实际破坏情况，验证了筋-土间的摩擦作用是影响加筋挡土墙稳定性及其临界高度的重要因素。实际工程中，可增加筋材-土体间的摩擦系数来提高挡墙的稳定性，使设计更加优化。

Critical height research of reinforced retaining wall considering the friction loss

In the present design of critical height of reinforce retaining wall, the loss of friction between soil and reinforcement is usually neglected. In this study, an improved formula is proposed to calculate the critical height of reinforced retaining wall. This new equation is derived based on the upper bound theorem for limit analysis, which takes the three factors into considerations in the internal failure of reinforced retain wall: (i) the rates of energy dissipation of reinforcement, (ii) the rates of energy dissipation of soil along the velocity discontinuity surface, and (iii) the rate of friction loss along their interface. This theoretical equation is tested against the data from a centrifugal test. The results calculated using the proposed formula are in closer agreement with the measurements/observations in the centrifugal than those existing equations, in terms of both the critical height and the failure mechanism, indicating the important influence of soil-reinforcement friction on the stability and design of critical height of reinforced retaining wall. The results presented in this study has some important practical implications, the stability of retaining wall could be improved by increasing friction coefficient, for the purpose of optimization of design of reinforced retaining wall.