Cfg Pile Composite Foundation Theory And Engineering Application Research

Now, with the economic development and the extending scale of the civil engineering construction, the disposing to original foundation has been more and more taken into account as a segment in designing and working. The method of Cement Flyash Gravel piles composite foundation has been widely used due to its great advantages such as the economizing,the fast speed and the fine effect on consolidating. Especially, the CFG pile composite foundation is able to improve ground bear ability highly, and it can also control deformation of buildings effectively. All these help that appliment scope of CFG pile composite foundation is being enlarged, from multi-storey buildings in initial stage to tall buildings gradually.With the research aim of applied in tall buildings, the dissertation systematically studied the CFG pile composite foundation , combining concrete engineering examples.Firstly, the research purpose,meaning,method and the research present situation of CFG pile composite foundation are carried on the summary. And the paper also discussed the characteristic, the working mechanism of CFG pile composite foundation, and detailedly analyzed the bearing bearing behavior of CFG pile composite foundation with vertical load. The paper drew the conclusion that due to the cushion course, the CFG pile composite foundation can improve ground bear ability highly, and decrease deformation effectively.Secondly, basing on the analysis of the design philosophies for CFG pile composite foundation, the paper detailedly analyzed and compared the calculated method for bearing capacity and settlement of CFG pile composite foundation, and drew some conclusions. For the calculating of bearing capacity, the paper suggested using the "Niuzhirong" formula, but must revise the safety factor "k" and the improve factor "a", the "k" is fit for 1.2 to 1.5, the "a" is fit for 1.0 to 1.2. For the calculating of settlement the paper think that the ES method's result has some error, the numerical value caculating method is very difficult and the criterion method should be reformed.Again, the paper researched the construction of CFG pile composite foundation at the foundation of the author's work experience; analyze the construction keystone, check-up, check and accept; compared and analyzed the construction technics, and summarized the guaranteed measure for construction quality. With the concrete engineering examples, the paper researched the construction period and compared it with the familiar pile foundation, transpired that the CFG pile composite foundation has more advantage than the familiar pile foundation.Finally, the paper systematically and thoroughly analyzed the engineering example of tall building at the base of foregoing study, from the choosing of project to design, construction, evaluating and check-up of settlement, and summarized that the CFG pile composite foundation held the vastitude developed foreground, we should energetically extend and apply. However, the research theory of CFG pile composite foundation is lacking and should has more research, especially in the reliability,check-up and so on.