爆炸荷载作用下钢筋混凝土梁变形指标限值研究

摘要

The key steps for component performance-based design under blast loading are the estimation of the structural performance level and the nonlinear analysis after reinforcement yielding. The quantitative criteria of the deformation pro-perties for structural components are not given in current Chinese code for blast-resistant design. The relationship between ductility ratio and the structural performance level can be established via quantities of tests or numerical simulation. By utilizing hydrocode LS-DYNA,the influence of the parameters on the failure modes and the deformation limits of RC beams under blast loading can be analyzed. Based on the interpretation of numerical simulation,the failure modes of RC beams is divided by shear-moment ratio and the bending and shearing deformation limits criterion are based on displacement ductility coefficient and shear-moment ratio.%基于构件性能的抗爆设计的关键是正确地评估爆炸作用下结构的损伤程度、变形需求及进行屈服后的非线性变形分析.现行抗爆设计规范并未给出构件具体的变形限值,而通过大量的试验或模拟计算可以得到构件延性比与性能水平的关系,建立这样一层关系就可以利用现有规范中的等效静载法实现多性能目标的结构抗爆设计.利用LS-DYNA有限元软件对大量爆炸荷载作用下RC梁的破坏形态、变形指标限值及影响因素进行了研究.根据有限元分析结果,依据剪弯比划分了 RC梁破坏形态,并进一步依据位移延性系数、剪弯比等分别给出了 RC梁弯曲破坏和剪切破坏的各性能水平的变形限值.