充水高密度聚乙烯波纹管爆破振动动力响应特性

Dynamic response characteristics of water-filled high density polyethylene corrugated pipelines under blasting vibration

为研究爆破振动作用影响下高密度聚乙烯(high-density polyethylene, HDPE)波纹管的动力响应特征,通过现场预埋HDPE管道的爆破试验,对不同爆破距离条件下的HDPE波纹管的振动特性进行分析。结合LSDYNA有限元数值模型分析方法,建立试验的数值模型以及充水状态管道的数值模型,研究了充水状态HDPE管道在爆破振动作用下的动力响应,并结合规范给出参考的安全判据。研究表明,爆破振动作用下,充水管道的振速值略小于无水管道的振速值,管道内的水能一定程度上降低爆破振动对管道的影响;管道各截面处迎爆侧的振动速度和von-Mises有效应力均大于管道背爆侧,管道底部附近的动力响应值较大,且管道峰值有效应力与管道峰值振动速度之间具有线性函数关系;不同埋深情况下,管道振速与地表振速之间存在函数关系,结合规范中管道最大允许工作压力以及管道应力与振动速度的函数关系,得到该场地条件下不同管道埋深的HDPE波纹管(充水)的地表爆破控制振速,为工程实际提供指导。

To investigate the dynamic response of HDPE corrugated pipeline under blasting vibration,blasting experiments on embedded HDPE pipeline were conducted,and the vibration characteristics of HDPE pipelines with different blasting distances were analyzed.Furthermore,based on the finite element software LSDYNA,the numerical model for field test and the numerical model for water-filled HDPE pipeline were established,so that the dynamic responses of water-filled HDPE pipe under blasting vibration were studied,and the safety criterion of the HDPE pipeline was proposed according to the Code.The results show that under the blasting vibration,the vibration velocity value of water-filled HDPE pipe is slightly less than that of water-free pipeline,indicating that water in the pipeline can reduce the impact of blasting vibration to a certain extent.Both the vibration velocity and von Mises stress at the blasting side of each section of the pipeline are greater than those of the back blasting side of the pipeline,and the vibration response of the pipeline is relatively larger near the bottom of the pipeline.In addition,there is a linear function relationship between the peak von Mises stress and the peak vibration velocity of the pipeline,and under different burial depths there is a functional relationship between the pipeline vibration velocity and the surface vibration velocity.Based on the maximum allowable working pressure of pipeline in the Code and the functional relationship of pipeline stress and vibration velocity,the controlled vibration velocity of HDPE corrugated pipelines(water filled)with different burial depth under the site conditions is obtained,which provides guidance for engineering practice.