非饱和土临界荷载和太沙基极限承载力解析解

Analytical Solutions of Critical Load and Terzaghi’s Ultimate Bearing Capacity for Unsaturated Soil

摘要:

基于非饱和土双应力状态变量抗剪强度统一解,综合考虑中间主应力、基质吸力和超固结比等影响,推导了非饱和土条形地基临界荷载和太沙基极限承载力解析解,并得出统一强度理论参数、基质吸力和超固结比对解析解的影响规律.研究结果表明：该解析解具有很好的可比性,临界荷载公式适用于任意侧压力系数；临界荷载和太沙基极限承载力均随着统一强度理论参数和基质吸力的增大而显著增加；临界荷载与超固结比近似成线形递增关系,不同基质吸力所对应的临界荷载间相互平行.

Abstract:

Based on the unified solution of shear strength for unsaturated soil in terms of two state stress variables,analytical solutions of the critical load and Terzaghi’s ultimate bearing capacity for unsaturated soil strip foundation are obtained by taking into consideration the influences of intermediate principal stress,matric suction and overconsolidation ratio.The influence laws of the unified strength theory parameter,matric suction and overconsolidation ratio on the analytical solutions are discussed.The results show that the analytical solutions obtained in this paper have a good comparability to many existing results; the formula of critical load can be suitable for any lateral pressure coefficient; the critical load and Terzaghi’s ultimate bearing capacity increase significantly with the increasing of the unified strength theory parameter and matric suction; there is a linear increase relationship between the critical load and overconsolidation ratio,and the critical loads corresponding to different matric suction are parallel to each other.