Soil Failure Mode of a Buried Pipe Around in Soil Undergoing Lateral Movement

측방변형지반속 매설관 주변지반의 파괴모드

A series of model tests is performed to evaluate the relationship between soil and a buried pipe in soil undergoing lateral movement. As the result of the model tests, a wedge zone and plastic flow zones could be observed in front of the pipe. And also an arc failure of cylindrical cavity could be observed at both upper and lower zones. Failure shapes in both cohesionless and cohesive soils are nearly same, which was investigated failure angle of $45^{\circ}+{\phi}/2$. In the cohesionless soil, the higher relative density produces the larger arc of cylindrical cavity. On the basis of failure mode observed from model tests, the lateral earth pressure acting on a buried pipe in soil undergoing lateral movement could be applying the cylindrical cavity extension mode. The deformation behavior of soils was typically appeared in three divisions, which are elastic zones, plastic zones and pressure behavior zones.