실내모형시험을 통한 상대밀도가 다양한 사질토 지반에서의 하수도관 파손에 따른 지표침하의 영향범위에 관한 연구

It is well known that water leakage from decrepit sewer pipe mainly causes frequent occurrence of ground subsidence in urban area. Thus, laboratory model tests were carried out to investigate ground behaviour according to location of sewer fracture and various relative densities of surrounding soil. The portion of fractured pipe was assumed to be 20% compared to the circumference of pipe, and to be positioned at the top and bottom of the pipe. Ground conditions were made as loose sand ($D_r=30%$) and dense sand ($D_r=70%$). In addition, comparison and analysis with results of model tests were carried out by Finite Element analysis. As a result, not only water leakage from the bottom of pipe (scenario 2) caused greater ground behaviour than leakage from the top of pipe (scenario 1), but also much greater surface settlement occurred when the ground condition is loose.