Abstract: In current researches, p-y curve is widely used to study the deformation properties of lateral thrust piles when surrounding soils are unexcavated, but is rarely applied to calculate the deformation of the ditch enclosure structure of deep foundation. With the nonlinear displacement of soil into consideration, the method of p-y curve is in accordance with the actual state of the inner soil which is compacted by the foundation ditch enclosure structure. In view of this, the displacement of the ditch enclosure structure of a practical engineering project was calculated by using p-y curve method, and was compared with measured result and the calculation result of the incremental analysis method for beam on elastic foundation to verify its rationality and superiority. Results unveiled that the lateral displacement calculated by p-y curve method is closer to measured displacement than the result calculated by the incremental analysis method for beam on elastic foundation. In addition, the displacement curve obtained by p-y curve method is in line with the actual deformation law of the ditch enclosure structure of deep foundation. Both theory and practice have proved that p-y curve method is rational in calculating the displacement of the ditch enclosure structure of deep foundation.

Key words: foundation pit, support structure, p-y curve, displacement, incremental analysis method for beam on elastic foundation