摘要
在碰撞冲击荷载下,钢筋混凝土结构的动态响应及损伤破坏过程是一个复杂的非线性过程。运用LS-DYNA建立了钢筋混凝土柱的三维分离式模型,钢筋与混凝土的连接按粘结滑移进行处理。通过与共节点方法对比并检查系统能量关系,验证了粘结滑移模型的正确性。以刚性球与钢筋混凝土柱的碰撞冲击为例,研究了刚性球质量、初速度、混凝土轴心抗压强度、纵筋配筋率和箍筋配筋率等参数对钢筋混凝土柱动态响应的影响,并分析了冲击荷载下钢筋混凝土柱的破坏模式。结果表明:刚性球质量、初速度的增加都会不同程度地加剧钢筋混凝土柱的动态响应及损伤;在考虑混凝土应变率效应的情况下,提高混凝土轴心抗压强度并不能有效降低钢筋混凝土柱中点的水平位移;增加纵筋和箍筋配筋率均能有效提高钢筋混凝土柱的抗撞能力;冲击荷载下钢筋混凝土柱的破坏模式主要包括局部型破坏和整体型破坏。
The process of dynamic response and damage-failure for reinforced concrete （RC） structures subjected to impulsive load is a complicated nonlinear problem. A three-dimensional discrete model of one I^C column, in which the connections of steel bar and concrete are treated as bond slip, is established using LS-DYNA code. And the accuracy of the bond-slip model is verified through comparing it with the node sharing algorithm and checking system energy relations. Taking the collision of a rigid ball with the RC column as an example, the effects of rigid bali＇s mass and initial velocity, concrete strength, longitudinal and transverse reinforcement ratio on the dynamic response of the RC column are analyzed, and the failure mode of the RC column under impact is discussed. The results indicate that： the increasing of rigid bali＇s mass and initial velocity will increase the dynamic response and damage of the RC column; the lateral displacement of mid RC column can not be remarkably decreased by increasing concrete strength when the strain rate effect of concrete is considered; the increases of longitudinal reinforcement ratio and transverse reinforcement ratio can effectively improve the impact resistance capacity of the RC column; the failure modes of the RC column under impact include global and local failures.
出处
《工程力学》
EI
CSCD
北大核心
2013年第2期150-155,共6页
Engineering Mechanics
