摘要
通过引入考虑抗扭转和弯转的微观接触模型来模拟高内摩擦角的土体材料(如月壤、碎石),并以应力加载法进行正方形、圆形和条形基础的静载荷试验三维离散元模拟,分析不同基础形状对地基承载力、基底应力分布和地基破坏模式等影响规律,并将模拟结果与已有经验公式对比验证。结果表明:条形基础下的地基承载力和基底反力系数最大,圆形基础下最小;条形基础下地基呈现整体剪切破坏模式,而方形和圆形基础下地基呈现局部剪切破坏模式;基底应力由内而外呈现抛物线-马鞍-倒抛物线形变化,与刚性基础-土体相互作用理论一致;基于沉降控制法确定的圆形和方形基础形状系数分别为0.67和0.76,与太沙基理论解和Debeer公式相近(均小于1),与Meyerhof公式和Lyamin等公式相反(均大于1)。模拟结果可为高内摩擦角土体的形状系数修正提供参考。
A micro-contact model which takes the torsion and bending resistances into consideration was employed to simulate the high frictional soil(e.g., lunar soil, broken stone). Then three plate loading tests were simulated by the three-dimensional discrete element method with square, circular and strip plates using stress loading method, where the effect of plate shape on the bearing capacity, stress distribution beneath the plate and failure model in the ground were analyzed. In addition, the calculated shape factors were compared with those predicted by several existing solutions. The results show that the bearing capacity and reaction coefficient with strip plate are the largest, while those with the circular plate are the smallest;the general shear failure mode is observed for the strip plate while local shear failure mode is observed for the square and circular plate. The stress distribution under the plate undergoes a parabolic, saddle and inverted parabolic evolution, which is consistent with that predicted in rigid foundation-soil interaction theory. The calculated shape factors of square and circular plates are 0.67 and 0.76 respectively by controlling the settlement, which are similar to those predicted by Terzaghi method and Debeer formula(less than 1), while contrary to those predicted by Meyerhof formula and Lyamin formula(greater than 1). The results can provide advices for the determination of the shape factors on high frictional soils.
作者
奚邦禄
蒋明镜
张振华
刘笑显
XI Banglu;JIANG Mingjing;ZHANG Zhenhua;LIU Xiaoxian(College of Civil Engineering,Hefei University of Technology,Hefei,Anhui 230009,China;School of Civil Engineering,Suzhou University of Science aiul Technology,Suzhou,Jiangsu 215009,China;Anhui Key Laboratory of Civil Engineering Structures and Materials,Hefei,Anhui 230009,China)
出处
《水利与建筑工程学报》
2023年第1期117-123,共7页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金(52209127)
安徽省自然科学基金(2208085QE177)
中央高校基本科研业务费专项资金(JZ2021HGTA0154,PA2021GDSK0079)。
