The Aseismatic Properties Analysis About The Cement Fly-ash Gravel Pile Composite Foundation

Along with the progress of science and technology, there appeared the positive earthquake-resisting thought gradually in the prevention and cure methods of the paroxysmal earthquake disaster, to be brief, some facilities are be used in the frameworks what can consume some of the seismic energy, so there are little energy transferred to constructions above. The vibration respond of such constructions be controlled within the scope of admission, then There is little paroxysmal earthquake disaster arising. The special construction of the cement fly-ash gravel (abbreviated to CFG) pile composite foundation embodies this kind of thought which has some good aseismatic properties.Only considering the lateral earthquake, the differential equation of motion for the cushion can be derivated by using the new method of shearing force layer after the lateral shearing force replaces the seismic effect of super-structure. As the example's analytical conclusion which is drawn using the program which has developed with the Visual Basic computer language, the lateral shearing force is reduced almost to moiety becauce of the grain's resetting and shearing transform in the cushion, and the relative lateral displacement between upside and underside of the cushion is very litlle, acting oppsite to the true lateral displacement of the cushion's underside. Therefore, it do not magnify the earthquake-induced motion of super-structure, and it improves aseismatic properties of the whole CFG pile composite foundation contrarily.The lateral shearing force that the underside of the cushion is subjected to is distributed between the top of the CFG pile and the soil. In view of the change of the pile's internal force and distortion which induced by the strong earthquake, and making use of the improved method of foundation soil's horizontal force, the differential equation of motion for the pile can be derived if there is liquefied layer or not. Then introducing the initial conditions, and using Laplace transform and inverse transform, the expression of the pile's internal force and distortion can be derived. So the behaviour of load-transfer mechanism for a single pile and soil will be reflected.The effect that the CFG pile reinforces liquefiable soil layers will be fully considering in the analysis of ground layer liquefaction. Method for liquefaction discrimination of CFG piles composite foundation is also proposed herein, that is, the critical standard penetration hammer number will be reduced properly. CFG piles composite foundation is a new method of soft foundation's treatment. It is worthy to use definitely in the earthquake-prone regions, because it has some good aseismatic properties.