Abstract:A new hyperbolic p-y curve was derived to generally simulate then onlinearity of piles in layered soils, and the new p-y curve was presented containing parameters such as the initial ratio of elastic foundation coefficient, the initial elastic foundation coefficient,characteristic value of lateral displacementfor soils, and etc.. Model test of six timber piles and two steel piles in two groups settled in layer soils with upper clay and lower sand were done. The calculated lateral displacements of model piles both at the top and at the ground are consistent with the test values by p-y curve method, and the new hyperbolic p-y curve is verified. While the characteristic value of lateral displacement for layered soils increases, the displacement and the maximum bending moment of the pile decrease, the maximum shear and the maximum soil pressure around the pile increase. The variety of characteristic value of lateral displacement for the lower sand has extremely small effect on mechanical property of the pile, then the characteristic value of lateral displacement for lower soils can be defined as the same as that of the top soil during engineering application.