Liquefaction-induced settlement and lateral spreading effects on buried pipelines by using shaking table tests

Due to the importance of buried pipelines, as one of the types of lifelines, it is necessary to consider all possible seismic hazards in their operation. Settlement and lateral spreading caused by liquefaction are among these risks. In this research, their effects have been investigated using two series of 1-g shaking table tests. Results show that the maximum displacement applied to the pipe occurs during the shake is greater than the residual displacement after the shake. Also, by investigating the shear stress-shear strain curves (hysteresis loop), the reduction of shear stiffness due to the shake was observed. After liquefaction occurs, the soil loses its shear strength and the slope starts to move downstream. It is observed that the contribution of cyclic strains due to ground vibration is far less than the contribution of strain due to monotonic displacement. According to the findings of this research, the deformation of the pipe is less than the settlement of the ground due to the liquefaction.