基于Struik模型的聚乙烯管道蠕变行为分析

Analysis on Creep Behavior of Polyethylene Pipeline Based on Struik Model

结合聚乙烯管道长期负载的变形情况,对其蠕变行为进行研究。基于管道的Struik模型进行回归分析,求得时间硬化蠕变模型参数,建立了有限元模型。对管材在不同压力、不同壁厚下的蠕变情况进行了模拟,并在恒定压力下进行了试验,分析了管道的蠕变规律。结果表明,对于实验中研究的φ110×1.6 MPa型号的聚乙烯管道,蠕变随压力的增大而增大,压力每增大0.2P_(N),蠕变量增大约0.5%;增大聚乙烯管道的管壁厚度,环向蠕变逐渐减小,当管壁厚度由5 mm增大至10 mm时,100 h内的环向蠕变量减少了11%;有限元模拟结果与实验结果基本一致。采用时间硬化蠕变模型可以有效地进行聚乙烯管道蠕变有限元模拟,对聚乙烯管道设计与工程应用具有一定的指导作用。

According to the deformation of polyethylene pipeline under long-term load, the creep behavior of polyethylene pipe was studied. Based on the Struik model of pipes, the parameters of time hardening creep model were obtained by regression analysis, and the finite element model was established. The creep of pipes under different pressures and wall thicknesses was simulated and tested under constant pressure to analyze the creep law of pipes. The results showed that: For the φ110×1.6 MPa polyethylene pipes, its creep increased with the increase of pressure;and the creep variable increased by about 0.5% for each 0.2P_(N) increase of pressure;When the pipe wall thickness of polyethylene pipe was increased, the circumferential creep decreased gradually. When the pipe wall thickness was increased from 5 mm to 10 mm, the circumferential creep decreased by 11% within 100 h;The finite element simulation results were basically consistent with the experimental results. The time-hardening creep model could effectively carry out the finite element simulation of polyethylene pipeline creep, and had a certain guiding role for the design and engineering application of polyethylene pipeline.