广义复合地基理论及工程应用

首先通过对复合地基技术发展过程的回顾,阐述了从狭义复合地基概念到广义复合地基概念的发展过程。通过分析浅基础、桩基础和复合地基三者在荷载作用下的荷载传递路线,指出复合地基的本质是桩和桩间土共同直接承担荷载,并讨论了三者之间的关系。接着分析了复合地基的形成条件以及满足形成条件的重要性。分析了复合地基与地基处理、复合地基与双层地基、复合地基与复合桩基之间的关系。讨论了基础刚度和垫层对桩体复合地基性状的影响、复合地基位移场的特点、复合地基优化设计思路和复合地基按沉降控制设计思路。介绍了工程中常用的复合地基型式、复合地基承载力和沉降计算实用方法。通过一个工程实例介绍了广义复合地基理论在高速公路工程中的应用。最后还对进一步应重视的研究方向提出建议。

Generalized composite foundation theory and engineering application

Firstly, the development of the generalized composite foundation theory was expounded based on a review of the development of composite foundation techniques. Through the comparison among the load transfer mechanisms of shallow foundation, pile foundation and composite foundation, it was pointed out that the essence of the composite foundation was that both piles and soils bearer the loading together directly, and the relationship among the above three foundation types was discussed. Then the forming condition of composite foundation and the importance of forming condition were studied. The relationship of composite foundation and ground treatment, composite foundation and double-layered foundation, composite foundation and composite pile foundation were studied. The influence of the foundation rigidity and the bedding cushion on the behavior of composite foundation, the characteristics of the displacement field of composite foundation under loading, the principle of the optimum design of the composite foundation and the design of composite foundation according to settlement were discussed. Type of composite foundation, practical methods to calculate the bearing capacity and settlement of composite foundation were introduced. A case study of the application of the generalized composite foundation theory to highway engineering was discussed. Finally, some proposals concerning further development of the generalized composite foundation theory and its application were put forward.