Settlement Analysis Of Composite Ground With Cement-mixed Columns Under Building

The settlement of composite ground after construction has been received more and more attentions. In this thesis, a detailed study is made on the settlement of composite ground with cement-mixed columns after construction of building through theoretical and numerical as well as case analysis and comparisons.Firstly, the development history of composite ground is reviewed, and the status of study and application of composite foundation with cement-mixed columns introduced. Then available methods for the computation of settlement of composite ground are listed. On this basis, the applications of FEM computer code PDSS in consolidation and settlement analyses are illustrated by comparing the FEM results with the analytical ones for one or two dimensional consolidation problems. Further more, the computer code PDSS is used to analyze the consolidation process of composite ground with cement-mixed columns under one teaching building and under one laboratory building, respectively, and the principle of the developments of excess pore water pressure in these composite ground and of the settlement is revealed. Finally, the FEM results are compared with the ones obtained from traditional method and field observation, and the feasibility of using PDSS to calculate the settlement of composite ground with cement-mixed columns after construction of building is discussed.It has been shown that it is very important to estimate and control the settlement of composite ground with cement-mixed columns after construction of building, and the computer code PDSS has provide an effective way for the computation of the settlement of such composite ground.