Abstract: Three dimensional numerical analyses are performed on a pile group model. Based on the analysis and comparison of a pile group testing model using numerical simulation in 3dimension, models of a single friction pile and friction piles group with embedded cap were built, and the similarities and differences of their behaviors were revealed by numerical simulation method. The results showed that under the same conditions, the type of loadsettlement curves and the development of the shaft resistance of the single pile and pile group foundations were respectively different; the upper loading was not simply allotted to each pile of the pile group averagely; a socalled "strengthen effect" of shaft resistance on each pile would occur near the end of the pile; and a socalled "weakeneffect" would be caused on the upper part of each pile. These laws revealed in the paper coincided with what people have known in theory or the measurements, which showed that analysis on the behaviors of friction pile groups by numerical simulation method was feasible, and could be references for the design calculations of pile groups.

Key words: Numerical Analysis, Friction Pile Groups, Behavior, LoadSettlement Curve, Friction Resistance