With the continued increase in surface areas of pit excavation

a type of combined support structures of piles and oblique bracing has been developed.Based on a two-stage method

the Winkler’s model was adopted to simulate the effect of pile-soil interaction while the characteristics of multi-layered soils was taken into account with the finite difference method.Then

with the simplified Mindlin’s solution for piles subject to lateral loadings

the pile-pile interaction of the combined support structure was considered to calculate the shielding effect of the structure

to develop a simplified analytical scheme for the investigation of the lateral response of piles of the support structure in the process of excavation.Finally

the characteristics of force and deformation of the combined support structure of piles and bracing was studied for a real project in Jinan city with the finite difference method.The study has shown that the combined support structure can effectively transfer external loads to the pit’s soil

and balance well the deformations of the soil and the support structure through proper arrangement of piles and bracing.