Laboratory evaluation of buried high-density polyethylene pipes subjected to localized ground subsidence

Abstract

Laboratory evaluation of buried high-density polyethylene pipes subjected to Laboratory evaluation of buried high-density polyethylene pipes subjected to localized ground subsidence localized ground subsidence Abstract AbstractThe serviceability loss of buried high-density polyethylene (HDPE) double-wall corrugated pipes caused by localized ground subsidence has been reported all over the world. Beam-on-nonlinear spring model is widely used to analyze the structural responses of buried pipes to the localized ground subsidence underneath the pipe. However, the pipe-soil separation is not considered by the beam-on-nonlinear spring model which assumes bonded interaction between the pipe and soil. This is because the spring stiffness could not be assigned as zero. The bonded interaction between pipe and soil is not able to capture the pipe behavior and characteristics of load distribution around the pipe when pipe-soil separation occurs. This study presents a series of large-scale model tests aiming to investigate the performance of buried HDPE double-wall corrugated pipes subjected to the localized ground subsidence. Movable plates installed at the bottom of the model test box are lowered down to simulate the localized ground subsidence. Earth pressures, pipe vertical displacements, and settlements at the backfill surface are monitored. For comparison purpose, free field condition (i.e., without pipe) is also tested. The test results demonstrate that soil settlement troughs above buried pipes are shallower and wider than those at the same elevation in the free field condition. Earth pressures at the top of the pipe are found to increase due to the negative soil arching, i.e., earth pressure is greater than the overburden pressure. It is suggested that three-dimensional soil arching, i.e., soil arching effects in both the transverse and longitudinal directions of the tested pipe, should be considered in calculating the earth pressures at the pipe top. The pipe-soil separation is substantiated by the observation that earth pressure measured at the bottom of the pipe is zero. Finally, empirical equations are proposed to correlate the volume of pipe displacement profile with the volume of settlement trough at the backfill surface to facilitate evaluation of the performance of the pipes subjected to the localized land subsidence. Abstract:The serviceability loss of High Density PolyEthylene (HDPE) double-wall corrugated 32 pipes caused by localized ground subsidence has been reported all over the world. Theory of beams 33 on Winkler elastic foundation is commonly used to analyze structural responses of buried pipes 34 subjected to ground subsidence. However, the theory of beams on Winkler elastic foundation 35 assumes that the displacement of buried pipes exactly matches the soil settlement trough (i.e., the 36 displacement of pipe is equal to the soil settlement underneath the pipe). This assumption is not able 37 to present the pipe behavior and load distribution around the pipe when pipe-soil separation occurs a...

Experimental and numerical study of shallow‐buried high‐density polyethylene pipeline under collapse touchdown impact

“…According to the size of the soil box in the experiment, a rammer-tube-soil three-dimensional finite element model with a buried depth of 25 cm was established in the commercial finite element software ABAQUS. 16 The size of the soil model was 1 m in length and width and 0.7 m in height. The drop hammer size was 22 cm × 15 cm × 12 cm.…”

“…Liang et al 13 studied the distribution of stress, strain, and displacement in buried PE pipes under above-ground loading. Wu et al 14,15 and Zhou et al 16 studied the mechanical behavior of gas PE pipes and HDPE double-wall corrugated pipes under land subsidence. Fei et al 17 studied the time-dependent performance of steel-reinforced HDPE (SRHDPE) pipes and developed an empirical relationship between vertical arching factor and the equivalent stiffness coefficient.…”

Mechanical Behavior of Polyethylene Pipes under Strike-Slip Fault Movements

“…On the other hand, only a small number of research work have been conducted for the investigation of PE pipe under fault displacement [ 21 , 22 , 23 , 24 , 25 , 26 , 27 ]. Xie et al performed a systematic study on the response of buried PE pipe to strike-slip faulting using shell elements and spring elements to model the behavior of pipe and soil.…”

Numerical Investigation of the Short-Term Mechanical Response of Buried Profiled Thermoplastic Pipes with Different Diameters to External Loads

“…Kang et al (2013Kang et al ( , 2014 analyzed the maximum and minimum burial depths (cover) allowed for using thermoplastic pipes in highways by evaluating deflection and stress criteria of pipes [15,16]. Zhou et al (2019aZhou et al ( , 2019b presented a series of large-scale model tests aiming to investigate the performance of buried HDPE double-wall corrugated pipes subjected to the localized ground subsidence and fault movement [17,18]. Talesnick et al (2011) embedded a pressure sensor in the pipe wall to measure the radial Earth pressure and deflection of the HDPE pipe when the static load acted on the ground surface.…”