Test Study Of Pile Composite Foundation In Mu Us Desert

Through in-situ tests and testing method in Mu Us Desert, this paper study on the bearing capacity characteristics of several common sand piles, cement-soil mixing piles and gravel piles composite foundation on aeolian sand layer, obtaining the critical edge pressure of the pile body, the soil between piles and the composite foundation itself in the composite foundation which consists of sand piles, cement-soil mixing piles and gravel piles, also getting the ultimate bearing capacity of the soil between piles and the pile body in sand pile composite foundation, the limit bearing capacity of cement-soil mixing piles body and the soil between gravel piles. And then, this paper giving the ultimate bearing capacity of the composite foundation which is composed of the three piles mentioned above by calculating, the results that combine the test with calculate result can be used in engineering practice of design and construction in Aeolian Sand strata's composite foundation, which provide an important test parameters can be reference for design in Mu Us Desert.This paper also studied the effective length of single pile and the characteristics about how effective load sharing between piles and the soil around in composite foundation by embedding pressure box and stress meter, and picked up the measured values of the effective length of single pile, on this basis, this paper summaried up the rule on how effective load sharing between piles. The related knowledge for Mu Us Desert's Aeolian Sand strata's composite foundation to engineering practice has the important instruction maening.On the basis of the achievements by field loading test, this paper use the finite element analysis software of Midas-GTS to give the numerical simulation in situ load test each working condition about sand piles, cement-soil mixing piles and gravel piles to disclose the deterioration forms and traits of the pile bodies and composite foundation itself under loading test, and accordingly this to definition the theory limit load about the single gravel pile composite foundation and the composite foundation.