Technical code for design of building foundation and technical code for building pile foundation prescribe the minimum pile spacing of every kind of piles, which ensure that the designed pile spacing is close to the pile spacing of the maximum effect for pile group in order to get a higher effect for pile gr.

Reasonable pile spacing in the design of pile foundation;

A theoretical criterion for judging the failure mechanism occurring below the base of pile groups is presented and the values of bearing capacity coefficients N_q and N_y which take account of the effect of rough or smooth base, pile spacing and angle of pile tip are obtained by means of an rigid-plastic model in this paper.

Anti-liquefied effect of different pile spacing foundation is explored through shaking table test,and some questions are proposed.

The study of proper piles spacing in row piles retaining and protecting structure based on horizontal soil arching effects;

Based on the analysis of the soil arch effect between adjacent anti-sliding piles in some slope projects,it is proposed that the relation between the piles spacing and the cohesive force c as well as the internal friction angle of the soil behind piles can be found,and the suitable spacing can.