基于统一强度理论的临坡加筋地基极限承载力新解  

A new solution to the ultimate bearing capacity of reinforced foundation near slope based on the unified strength theory

作　　者：晏青[1] 赵均海[1] 张常光[1] YAN Qing;ZHAO Jun-hai;ZHANG Chang-guang(School of Civil Engineering,Chang’an University,Xi’an,Shaanxi 710061,China)

机构地区：[1]长安大学建筑工程学院,陕西西安710061

出　　处：《岩土力学》2021年第6期1587-1600,共14页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51878056);陕西省科技计划-社会发展领域项目(No.2019SF-256);地质灾害防治与地质环境保护国家重点实验室开放基金(No.SKLGP2020K022);长安大学中央高校基本科研业务费专项资金(No.300102289720)。

摘　　要：针对加筋地基整体剪切破坏和复合破坏两种模式,在统一强度理论的基础上,考虑中间主应力、筋材层间距、加筋层数和筋材抗拉强度的综合影响,推导了临坡条形基础加筋地基的极限承载力新解,并给出了应用步骤。通过与其他方法的对比,讨论了该方法的有效性和参数影响特性。研究结果表明:所得极限承载力解答与文献模型试验结果吻合良好,具有广泛的适用性;随着中间主应力效应的增加,整体剪切破坏和复合破坏下临坡加筋地基极限承载力均明显增大;随着筋材层间距的增加,整体剪切破坏下临坡加筋地基极限承载力先增大后减小,而复合破坏下逐渐减小;整体剪切破坏下加筋层数的影响分为3个阶段,复合破坏下分为2个阶段;同时,筋材抗拉强度的影响不可忽略。该研究结果可为临坡加筋地基的优化设计提供有益的参考。In view of two modes of general shear failure and composite failure of reinforced foundation, a new solution to the ultimate bearing capacity of strip footings resting on reinforced foundations near slope was derived based on the unified strength theory and the application procedures were given. Effects of the intermediate principal stress, the vertical spacing between reinforcement layers, the number of reinforcement layers, and the tensile strength of reinforcements were comprehensively taken into consideration in the new solution. Compared with other methods, the effectiveness and parameter influence characteristics of the proposed method were discussed. The results showed that the obtained solution to the ultimate bearing capacity of reinforced foundation agreed well with the results of model tests reported in the literature, and it had wide applicability. With the increase of the effect of intermediate principal stress, the ultimate bearing capacity of reinforced foundation near slope subjected to general shear failure and composite failure increased markedly. As the vertical spacing between reinforcement layers increased, the ultimate bearing capacity of reinforced foundation near slope increased first and then decreased under the general shear failure, but it would gradually reduce under the composite failure. The influence of the number of reinforced layers under the general shear failure can be divided into three stages, and that under the composite failure can be divided into two stages. Meanwhile, the effect of the tensile strength of reinforcements cannot be ignored. The research results can provide useful references for the optimization design of reinforced foundation near slope.

关 键 词：临坡加筋地基 极限承载力 统一强度理论 整体剪切破坏 复合破坏 

分 类 号：TU470[建筑科学—结构工程]