洪水灾害下管道的力学计算

Stress Calculation of Pipeline under Flood Disaster

为了研究流动水动力、浮力、管体以及输送介质重力、土壤地基抗力对管道的共同作用,建立洪水作用下的管道力学分析模型,选用数值分析方法和有限元方法计算了管道的应力及应变。结果表明,两种方法的计算结果较接近。依据该有限元模型,分析了洪水流速和穿越距离对管道应力及应变的影响。结果表明,当流速大于3.0m/s时,管道应力和应变随流速的增加趋势加大;当穿越距离增加时,堤岸处管道最大应力和轴向应变逐渐增大,但增幅逐渐减小;当穿越距离小于160m时,河流中部管道的应力和轴向应变随着穿越距离的增加而增大,当穿越距离大于160m时,应力和轴向应变随着穿越距离的增加而略有减小。对榆济线埋地悬空管道进行了安全评估,结果可知即时应力为178 MPa,悬空管道安全。

In order to study the interaction of flowing hydrodynamic force,buoyancy,pipe body,gravity of conveying medium and resistance of soil foundation on pipeline,the mechanical analysis model of pipeline under flood was established.The stress and strain of pipeline were calculated by numerical analysis method and finite element method.The results show that the calculation results of the two methods are close.Based on the finite element model,the effects of flood velocity and crossing distance on pipeline stress and strain are analyzed.The results show that when the velocity is greater than 3.0 m/s,the stress and strain of the pipeline increase with the increase of the velocity.When the crossing distance increases,the maximum stress and axial strain of the pipeline at the embankment gradually increase,but the increase decreases.When the crossing distance is less than 160 m,the stress and axial strain of the pipeline in the middle of the river increase with the increase of the crossing distance,and when the crossing distance is more than 160 m,the stress and axial strain decrease slightly with the increase of the crossing distance.The safety assessment of the buried suspended pipeline of Yulin Jinan Railway is carried out.The results show that the immediate stress is 178 MPa,and the suspended pipeline is safe.