Abstract: Taking the construction process of excavtion and supporting of the composite soil nailed wall of soil nailing and cement-soil piles for deep foundation excavation as the object of study,and using the nonlinear finite element software ADINA,a whole three-dimensional finite element model were established.Spatial action of foundation pit are considered in the model.The influence of different horizontal distance of nails and small prestress on the horizontal displacement of excavation face,the subsi...