中文摘要：

针对影响油气管道安全运营的落石冲击问题,基于弹塑性力学、Cowper-Symonds本构模型和有限元方法,建立了球形落石冲击油气管道的计算模型,对管道动态响应过程进行了数值模拟。对冲击速度、落石半径、管道内压力和落石冲击位置进行了参数敏感性分析,研究了各参数对管道冲击变形的影响规律。结果表明：落石的冲击能量主要用于管道塑性变形;冲击过程中,落石与管道的接触区域由初始的椭圆斑逐渐变成了椭圆环;管道塑性变形随着冲击速度和落石半径的增大而增大,随内压和落石偏移度的增大而减小。该研究工作为油气管道的安全评价及防护工程的设计提供了参考依据,对保障油气安全运输具有重要的工程意义。

英文摘要：

Aiming at the problem of rock- fall which influences the safe operation of oil and gas pipeline,based on the elastic- plastic mechanics,Cowper- Symonds constitutive model and finite element method,a calculation model of oil and gas pipeline impacted by rock- fall was established,and the dynamic response process of pipeline was numerically simulated. The parameter sensibility of impact velocity,radius of rock- fall,pipeline pressure and impact position of rock- fall was analyzed,and the influence rules of each parameter on the deformation of oil and gas pipeline were researched. The results showed that the impact energy of rock- fall is mainly used in plastic deformation of pipeline. In the impact process,the contact area between rock- fall and pipeline turns from elliptical spot to elliptical ring. The plastic deformation of pipeline increases with the increasing of impact velocity and radius of rock- fall,and it decreases with the increasing of pipeline pressure and deviation degree of rock- fall. The research can provide a reference basis for the safety assessment and protection engineering design of pipeline,and it has an important engineering significance to guarantee the safety transportation of oil and gas.