冲击载荷作用下埋地长输管道动力响应研究

由于土体的离散性较大,所以从理论上求解埋地管道在冲击载荷作用下的动力响应比较困难,且目前国内外关于埋地长输管道的试验研究也比较缺乏。鉴于此,从试验测试和数值模拟两方面出发,通过制作土箱-管道缩尺模型,进行埋地管道的冲击载荷试验,分析了埋地管道振动加速度的传播规律和应力应变分布情况。研究结果表明:随着距振源距离的增加,管道竖向方向振动加速度逐渐减小;通过试验研究和有限元数值模拟,可以得到在冲击载荷作用下管道竖向方向的振动加速度沿水平方向传播的近似关系式;在冲击载荷作用下,随着冲击高度的增加,管道应变峰值逐渐增大,且管道中部区域应变峰值最大,管道上、下表面应变呈反对称,沿管道两端方向,管道应变峰值逐渐减小;冲击载荷作用下埋地管道动力响应的有限元模拟结果与试验结果很接近。研究结果可为复杂工况下埋地管道抗冲击设计规范的制订提供参考。

Study on Dynamic Response of Buried Long Distance Pipeline under Impact Load

Due to the large dispersion of soil,it is difficult to theoretically solve the dynamic response of buried pipeline under impact load.Meanwhile,few experimental researches on buried long-distance pipeline are reported.In view of this,test and numerical simulation are conducted.The impact test of buried pipeline is carried out by the soil box-pipe scale model,so as to analyze the vibration acceleration propagation law and stress-strain distribution of the buried pipeline.The results show that the vibration acceleration in the vertical direction of the pipeline decreases with the increase of the distance from the vibration source.Through experimental research and finite element numerical simulation,the approximate relationship of the vertical pipeline vibration acceleration propagation in the horizontal direction is obtained.Under the impact load,with the increase of the impact height,the strain peak of the pipeline gradually increases,and reaches the maximum in the middle part of the pipeline.The strain on the upper and lower surfaces of the pipeline is anti-symmetric.The strain peak of the pipeline along the two ends of the pipeline decrease gradually.The finite element simulation results of the dynamic response of the buried pipeline under the impact load are very close to the experimental results.The study can provide a reasonable reference for the formulation of anti-impact design specifications for buried pipelines under complex conditions.