爆炸作用下钢筋混凝土梁动力响应数值模拟及破损分析

发布时间：2019-04-03 06:48

【摘要】：钢筋混凝土梁板类构件在爆炸作用下的动力响应和破坏模式是结构抗爆动力学研究的重要课题,具有十分重要的理论意义和工程应用价值。本文以爆炸作用下的钢筋混凝土梁为研究对象,研究了其在弹性支撑条件下的动力响应和影响其破坏形态的主要因素。主要内容如下:1、运用LS-DYNA软件对自由空气介质中爆炸冲击波的传播进行数值模拟,并与经验公式计算结果进行了对比,验证了本文中采用的数值模拟方法的适用性;对爆炸冲击波在刚性壁面上的正反射、规则斜反射、马赫反射的形成机理及反射冲击波在空气中的传播进行了数值模拟研究。2、对弹性支承梁均布荷载作用下的振型函数进行了公式推导,得出了此种情况下梁的振型;在一定假设条件下,采用第二类拉格朗日方程对弹性支承梁的运动方程进行了求解。3、通过ANSYS/LS-DYNA对参考试验中的钢筋混凝土梁进行了数值模拟分析,并将数值模拟结果与试验结果进行了对比,进而寻求更适用于爆炸荷载作用下的钢筋混凝土梁动力分析模型的建立方法。4、在以上研究成果的基础上,采用数值模拟方法对影响钢筋混凝土梁破坏形态的各影响因素进行了对比分析,主要包括爆炸荷载的加载速率、钢筋和混凝土材料的应变率效应以及构件的高跨比。
[Abstract]:The dynamic response and failure mode of reinforced concrete beam-slab members under explosion is an important subject in the research of structural anti-explosion dynamics, which has very important theoretical significance and engineering application value. In this paper, the dynamic response of a reinforced concrete beam under the condition of elastic bracing and the main factors affecting its failure form are studied by taking the reinforced concrete beam under the action of explosion as the research object. The main contents are as follows: 1. The numerical simulation of blast wave propagation in free air medium is carried out by using LS-DYNA software, and the numerical simulation results are compared with the empirical formula, and the applicability of the numerical simulation method used in this paper is verified. The formation mechanism of normal reflection, regular oblique reflection, Mach reflection and propagation of reflection shock wave on rigid wall are numerically simulated. In this paper, the modal function of the beam with elastic support under uniform load is derived, and the modal shape of the beam under this condition is obtained. Under certain assumptions, the second Lagrangian equation is used to solve the equation of motion of the elastic supported beam. 3. The reinforced concrete beam in the reference test is numerically simulated and analyzed by ANSYS/LS-DYNA. The numerical simulation results are compared with the experimental results, and then the establishment method of the dynamic analysis model of reinforced concrete beams under explosive load is found. 4, on the basis of the above research results, the dynamic analysis model of reinforced concrete beams under explosive load is established. The factors affecting the failure form of reinforced concrete beams are analyzed by numerical simulation, including the loading rate of explosive load, the strain rate effect of steel and concrete materials and the high-span ratio of members.
【学位授予单位】：哈尔滨工程大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU375.1

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