Abstract: For the internal force analysis considering structure-foundation-soil interaction of pile foundation, the results of the internal force analysis used in structural design should be judged whether or not the structural safety is ensured, and the calculation precision should be studied. Based on the measured results, when the interaction analysis results of pile foundation settlement distribution shape and value meet the regional measured results and the deviation between the input pile stiffness and the initial pile stiffness is less than 10%, the calculated results can be directly used for the internal force analysis of pile foundation. The calculation can use the following two methods: (1) integral rigidity of one-time forming pile; (2) integral rigidity of one-time or step load forming pile, segmented incremental calculation and final superposition calculation.