Shaking table tests on dynamic responses of pile group foundations for bridge was performed on 2×2pile group-low pile cap-single column pier system in liquefiable ground with 0.3moverlying clay layer and 1.2munderlying saturated sand layer.The test results show as follows:Firstly

the pore pressure

acceleration and displacement of soil mass decreases with increase of depth and as the input frequency increases

the pore pressure and acceleration of soil mass increase

but the soil mass displacement decreases.Secondly

the acceleration and bending moment of the pile increase from bottom to top

and the pile bending moment reaches its maximum near pile cap.As the input frequency increases

the pile bending moment decreases.Finally

with increase of depth

soil pressure and soil-pile relative displacement decrease and soil modulus presents increasing trend.Soil modulus and energy dissipation decrease as the input frequency increases.