Study On In-situ Soil Test And Pile Driving Of CFG Pile Composite Foundation

Nowadays,with the economic development and the extending scale of the civilengineering construction,the disposing to original foundation has been more andmore taken into account as a segment in designing and working. The method ofCement Fly-ash Gravel Piles composite foundation has been widely used due to itsgreatadvantagessuchas theeconomizingonmaterial,thefastspeedonworkingandthefineeffectonconsolidating,especially,theraisingandpracticingonthemultipledesigningmethods of Cement Fly-ash Gravel Piles composite foundation,which hasbeen played an important role in the development of the theory and practice ofcompositefoundationinrecent years.The bearing character and working mechanism of Cement Fly-ash Gravel Pilescomposite foundation are analyzed,following which the multiple designingmethodsand applying on projects are less comprehensively studied in this paper which arebased on the available scientific achievements of Cement Fly-ash Gravel PilesComposite foundation. Therefore,the main problems are studied in this paperhereinafter:At first,the computation formulas of the ultimate bearing capacity of thegranular material pile are discussed. The modified passive earth pressure method isput forward,it make the results more reasonable. Based on engineering practice andexperiment considering the lateral interaction of the pile and soil between Piles,thecomputation formula of bearing capacity of granular material piles proposed. By theparametric potential energy variational principle,the analytic solution of expansionproblem of granular material piles obtaioned. The common design methods ofgrammarmaterialpilecompositefoundationarediscussed.Secondly, analysis the mechanism properties,pile-soil stress ratio and itschangedruleof CFGcompositefoundation,Basedonthereactionofdifferentloads,computethecoefficientofthebearingcapacityofthesoilbetweenpiles.Based on the actual engineering, give detailed analysis on pile driving ofdifferent CFG piles. Put up the corresponding measures to control the quality of piledriving.According to the actual problem of how to control the height of the piles, put uptwo methods to resolve it. Study the orders of each construction, give the method toget the controlled lines. Also, exercise them according to the actual engineering, whichhasimportantmeaningtoguidethepiledriving.Finally,someproblemsofCementFly-ashGravelPilescompositefoundation,which remain to be Studied,are put forward on the basis of concluding theresearchingworksinthepaper.