Experimental investigation of water supply pipeline behavior in frozen soil

Abstract

Water supply pipelines are frequently damaged due to freezing problem every year. In order to reduce the damages resulting from such freezing and thawing cycles, pipelines, especially the water supply pipelines are buried below the depth of soil freezing to prevent the freezing of the roadbed. It was carried out to investigate the behavior of water supply pipeline laid underground in the winter season through a multi layered field model test. The ductile steel pipe and stainless pipe were used as the water supply pipe lines. The field experimental work was performed in the 3 different soil ground conditions. The strains on the water supply pipelines were measured in the field for both stainless pipe and ductile steel pipe. The results of field measured strain were compared with the results of simulated numerically strain. Based on the experimental test results, the contents of fine grained soil and degree of saturation as well as the soil temperature below zero are greatly influenced on the earth pressure on the water supply pipeline. The magnitude of earth pressure increases approximately in the range of 2.4~3.7 times with the variations of temperatures from 0℃ to -10℃. In the case of estimation of the total pressure applied over the water supply pipeline should be considered not only earth pressure by Marston and Spangler’s theory but also freezing pressure induced by the ground freezing.