Analysis on critical cyclic stress ratio and permanent deformation of composite foundation improved by cement-soil piles under cyclic loading

Through model tests on composite foundation of cement-soil piles under cyclic loading,and with interaction of cushion,reinforced zone and sublayer being taken into account,the vertical permanent deformation of composite foundation of cement-soil piles under cyclic loading was studied and the influences of consolidation states,cyclic stress ratio and vibration frequency were considered.The variation rule of critical cyclic stress ratio and vertical permanent deformation with numbers of loading cycles,vibration frequency and consolidation states were obtained.These results were siginificant to control the settlement of composite foundation.