复合加载下地基的承载特性是港口、海洋工程基础设计的关键问题。近来,极限荷载包络图取代了经典的承载力计算方法,用于评价复合加载下地基的组合极限承载力。以大型通用有限元软件ABAQUS为计算工具,对VM荷载作用下层状饱和黏土地基上基底完全粘结的条形基础承载力进行系统的变参数计算,研究地基土层强度特性、荷载组合等因素对地基承载力及破坏模式的影响规律,得出VM荷载作用下极限荷载的包络图,为港口、海洋工程基础设计提供参考。
The bearing capacity behavior of foundations under combined loading is one of the key issues in design of offshore structures. Recently, limit load envelope diagram is used to replace traditional calculations of limit bearing capacity to evaluate the combined limit bearing capacity' of foundations. In this paper, FEM parameter study of bearing capacity of foundations under VM loading is performed using software ABAQUS. And the foundations are simplified as footings on the surface of undrained two-layered saturated clay with unlimited tension between footing and subsoil. The effects of soil strength profile and combined loading on the subsoil capacity and failure mode are investigated. A limit load diagram under VM load is also presented and can be used to develop and improve the design of offshore foundations.