Cfg Pile Composite Foundation Traits And Its Engineering Applications

The theories and the applications of composite foundation are quite active in the past decade. the technology of composite foundation have been obtained bigger development. Because the composites reinforced in composite foundation are different, the load bearing mechanism of each kind of composite foundation is not all the same.CFG pile is the abbreviation of Cement Fly-ash Gravel pile, a kind of high bond strength pile made of cement, fly ash, reduced stone, rock chips and sand, mixed with water. It can be used to form composite foundation together with inter-pile soil and cushion course.With the merits such as economy,simple technics and good reinforcing effect, CFG pile composite foundation obtains the rapid promotion in our country, and has gained the good social and economic efficiency. But the theoretical study was far behind the practice. The main task of this dissertation has been gained are as follows:Firstly, the developing and researching situation of CFG pile composite foundation is reviewed in this paper, and analyzing the mechanism of load transferring and reinforce of CFG pile,and also analyzing the action mechanism of the cushion detailedly.Next, whereas the stong felt mechanism, we regarded as flexible pile, the ultimate capacity of CFG pile is calculated. We considered of lateral friction resisitance distributing, then a reasonable method of calculating ultimate capacity has been obtained. Linking the practice, we can drive to the formula of CFG pile composite foundation. The status and development of settlement analysis methods of CFG composite is summarized and compared in the paper.Next, Single pile composite foundation numerical analysis model is established by utilizing general FLAC3D mite differential program, the soil around piles module, soil under the pile module, cushion thickness, cushion module, pile length, replacement ratio and pile body elastic modulo are influential to settlement, soil under the pile settlement, compression of cushion and pile-soil stress ratio of the CFG foundation, these influences have been separately carried on the research.take The new passenger railway from Wuhan to Guangzhou as a example. Through the medium of scene static load test outcome,and comparing different kinds of calculation procedure,we thought the Dongbichang method's hypotheses is reasonal and the computational accuracy is high, so it possessed preferable applicability. Combining Flac3d to proceed numerical analysis,we can arrive that the sedimentation matching by the CFG pile composite foundation's theoretical equation is according with the analysis outcome by numerical value simulation. It show that the theory and empirical formula advanced by the text conform with the engineering practice.