ABSTRACT
Many buried structures, including tunnels and lifelines, have been severely damaged in recent earthquakes. It is noteworthy that the phenomenon of soil liquefaction has played a significant role in the occurrence of these damages. Damage caused by the uplift of lifelines has motivated the study of the uplift of buried structures. Therefore, in this study, an attempt has been made to experimental study of the uplift of buried pipes in liquefiable soils by physical modeling at different depths. The soil used in this study is Gum Tape sand and shaking table has been used to simulate seismic load. Buried pipe at three depths: 1.5, 2.5 and 5 times the diameter of the pipe has been subjected to seismic load and the degree of elevation and deformation mechanism have been investigated. The results show that with decreasing the buried depth of the pipe, due to the relatively high pore water pressure in the lower depth of the soil, the overpressure created after dynamic loading tends to be wasted and flows towards the low-pressure points (surface part). And because in the surface areas, the flow is upward, so the uplift continues to some extent. Also, the displacement vectors on the sides of the pipe are in the form of circular rings that try to raise the pipe.
