泥石流冲击荷载下带有腐蚀缺陷的圆钢管动力响应有限元分析

Finite Element Analysis of Dynamic Response of Round Steel Pipe with Corrosion Defects under the Impact Load of Debris Flow

考虑到泥石流拦挡坝长时间暴露在大气环境中易被腐蚀,利用ANSYS/LS-DYNA软件对拦挡坝中带有局部腐蚀缺陷的圆钢管构件抗冲击性能进行有限元分析,通过改变腐蚀深度、冲击物质量和冲击物速度等变量,对圆钢管构件的动力响应进行有限元分析,并对带有腐蚀缺陷的圆钢管构件进行CFRP局部加固分析。结果表明:随着局部腐蚀深度的增加,圆钢管构件腐蚀表面处的变形越来越明显,产生的塑性变形区域越来越大,并且由变形耗散的能量越来越高;在冲击物动能保持不变的情况下,圆钢管构件局部腐蚀深度越大,构件产生的冲击力越小,但构件发生的位移相差不大;在冲击物速度不变的情况下,未腐蚀的圆钢管构件产生的冲击力随着冲击物质量的增加而增大,而带有腐蚀缺陷的圆钢管构件产生的冲击力先增大后减小;在冲击物质量不变的情况下,冲击物速度越大带有腐蚀缺陷的圆钢管构件产生的冲击力越大;通过CFRP局部加固可以显著提高带有腐蚀缺陷圆钢管构件的抗冲击性能。

Considering that debris flow dams are prone to be corroded when exposed to atmospheric environment for a long time,this paper carries out finite element analysis of impact resistance of round steel pipe component with local corrosion defects in the debris flow dam with ANSYS/LS-DYNA.The paper conducts parameter analysis on the dynamic response of round steel pipe components by changing the variables of corrosion depth,mass and speed of the impact object.The paper also analyzes on the local reinforcement of round steel pipe component with corrosion defects by CFRP.Results show that with the increase of the local corrosion depth,the surface deformation of the corroded round steel pipe component becomes more and more obvious,the plastic deformation area becomes larger and larger,and the energy dissipated by the deformation becomes higher and higher.When the impact kinetic remains unchanged,the greater the local corrosion depth of the round steel pipe component,the smaller the impact force produced by the component,but the displacement of the component varies little.Under the condition that the speed of the impact object is constant,the impact force generated by the uncorroded round steel pipe component increases with the increase of the mass of the impact object,while the impact force generated by the round steel pipe with corrosion defect increases first and then decreases.Under the condition that the quality of the impact object is unchanged,the impact force generated by the round steel pipe component with corrosion defect increases with the increase of the speed of the impact object.The impact resistance of round steel pipe with corrosion defects can be significantly improved by CFRP reinforcement.