爆炸荷载下复式空心钢管混凝土柱的动态响应及损伤评估
发布时间：2019-07-02 10:36
【摘要】：随着国民经济的不断发展，由于燃气泄漏、易燃易爆品堆置不当、电器老化而引发的爆炸发生几率逐渐增大，致使建筑结构受到爆炸冲击作用的可能性随之增大。同时，由于全世界范围内恐怖袭击时有发生，爆炸对于建筑结构的威胁正与日俱增。要使结构在爆炸冲击荷载作用下有着较好的抗爆性能，避免结构破坏，柱本身的抗爆性能起着非常重要的作用。复式空心钢管混凝土柱具有承载力高、塑性好、抗弯刚度大的特点，被广泛用做工程结构中的重要受力构件。因此研究复式空心钢管混凝土柱的爆炸冲击破坏效应，进而建立其损伤评估方法具有重要的理论意义和工程应用价值。本文采用试验研究和数值模拟方法对爆炸荷载下复式空心钢管混凝土柱的动态响应和损伤评估进行系统研究，具有重要的理论意义和工程应用价值。主要的研究工作和创新成果包括以下几个方面： （1）研究了爆炸冲击波与复式空心钢管混凝土柱相互作用的数值模拟方法。基于显式动力学程序ANSYS/LS-DYNA，采用ALE流固耦合的加载方式建立了考虑地面反射的爆炸荷载下钢管混凝土柱、空气及炸药的有限元数值模型；进一步研究讨论了空气有限元网格划分对数值模拟结果的影响。结果表明网格尺寸大小对冲击波传播的波形和传播时间均有较大影响。冲击波压力峰值随着网格尺寸的增加呈下降趋势，网格密度越大，冲击波压力峰值与试验采集压力峰值越接近； （2）设计完成了两发钢管混凝土柱爆炸试验。通过对测点压力及柱宏观变形的分析，结果表明在折合距离为1.1m/kg1/3的第一发试验条件的爆炸荷载作用下，柱产生的变形属于弹性变形，没有塑性变形产生，柱仍有着良好的承载能力；在折合距离为0.14m/kg1/3第二发试验条件的爆炸荷载作用下，复式空心钢管混凝土柱迎爆面柱中发生了明显的塑性弯曲变形。柱迎爆面柱底肋板上缘柱表面有一条细微未贯通裂缝存在。结果表明柱端部节点强度与构件整体强度协调对提升复式空心混凝土柱的抗爆性能尤为重要； （3）研究了复式空心钢管混凝土柱各参数对爆炸冲击波与结构柱的相互作用以及作用于柱上爆炸荷载规律的影响。通过参数分析，，结果表明增大空心率可以使柱核心区混凝土承受的压力减小，从而在一定程度上改善复式空心钢管混凝土柱的抗爆性能；即使正压的作用时间一致，圆截面产生的压力值也要低于方截面，因此圆截面抗爆性能要优于方截面；提高混凝土强度等级对改善复式空心钢管混凝土柱的抗爆性能影响不大；折合距离变化对复式空心钢管混凝土柱的动态响应和抗爆性能有较大影响。柱迎爆面位移峰值的增加率随着折合距离的减小而迅速增加，压力峰值的增加率远大于折合距离的降低率，折合距离越小时，柱迎爆面压强变化也相应越敏感； （4）建立了基于复式空心钢管混凝土柱中弯曲挠度变形量的超压—冲量损伤准则。在进行大量数值模拟试算的基础上，建立了基于本文的复式空心钢管混凝土柱损伤等级分界线，即P-I曲线。并拟合建立了P-I曲线数学表达式。同时将所得公式推广到一般情况，建立了以迎爆面柱中挠度为指标的复式空心钢管混凝土柱弯曲变形损伤评估准则。
[Abstract]:With the continuous development of the national economy, the probability of explosion caused by the improper stacking of the gas and the combustible and explosive products and the aging of the electric appliance gradually increases, so that the possibility of the building structure being impacted by the explosion is increased. At the same time, the threat of the explosion to the construction structure is increasing as a result of the terrorist attacks worldwide. The structure has a good anti-explosion performance under the action of an explosion impact load, so that the structure is avoided, and the anti-explosion property of the column itself can play a very important role. The composite hollow steel tube concrete column has the characteristics of high bearing capacity, good plasticity and high bending rigidity, and is widely used as an important force component in the engineering structure. Therefore, it is of great theoretical significance and application value to study the explosion impact failure effect of compound hollow steel tube concrete column, and then to set up its damage evaluation method. In this paper, the dynamic response and damage assessment of the composite hollow steel tube concrete column under the explosion load are systematically studied by means of the experimental research and the numerical simulation method, which is of great theoretical significance and engineering application value. The main research work and innovative outcomes include the following aspects: (1) The numerical simulation of the interaction between the blast shock wave and the composite hollow steel pipe concrete column is studied. Methods: Based on the explicit dynamic program ANSYS/ LS-DYNA, the finite element numerical model of the steel tube concrete column, air and explosive under the explosion load of the ground reflection is established by the loading mode of the ALE flow-solid coupling, and the numerical simulation results of the air finite element mesh are further studied. The results show that the size of the mesh has a great effect on the wave and the propagation time of the shock wave. The peak of the shock wave pressure decreases with the increase of the grid size, and the higher the grid density, the higher the peak value of the shock wave and the peak pressure of the test. approach; (2) design of two steel-filled steel pipe concrete Through the analysis of the pressure of the measuring point and the macro-deformation of the column, the results show that under the action of the explosion load of the first test condition with the folding distance of 1.1 m/ kg1/3, the deformation of the column belongs to the elastic deformation, no plastic deformation is generated, and the column is still good The load-bearing capacity of the composite hollow-steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled concrete column has obvious plastic deformation under the action of explosion loading with a folding distance of 0.14m/ kg@@ The column is bent and deformed. The surface of the upper edge of the column bottom rib of the column-facing surface of the column is provided with a fine cross-section. The results show that the strength of the end node of the column and the overall strength of the component can be used to improve the anti-explosion of the composite hollow concrete column. The interaction between the explosion shock wave and the structural column and its action on the column are studied in (3). Through the analysis of the parameters, the results show that the increase of the hollow rate can reduce the pressure of the concrete in the core region of the column, so as to improve the anti-explosion performance of the composite hollow steel tube concrete column to a certain extent, even if the action time of the positive pressure is consistent, the pressure generated by the circular section The value is also lower than that of the square section, so the anti-explosion property of the circular section is superior to that of the square section, and the strength grade of the concrete is improved, the impact resistance of the composite hollow steel tube concrete column can not be greatly influenced, and the change of the folding distance on the dynamic response and the resistance of the compound hollow steel tube concrete column The rate of increase of the displacement peak of the column to the detonation surface increases rapidly with the reduction of the folding distance, the rate of increase of the pressure peak is much larger than the reduction rate of the folding distance, the more the folding distance is, the pressure of the column to the detonation surface The more sensitive the change is, (4) the deformation of the bending deflection in the concrete column based on the compound hollow steel pipe is established. Based on a large number of numerical simulation tests, this paper establishes the compound hollow steel pipe concrete column damage based on this paper. Class boundary, that is, the P-I curve. The mathematical expression of P-I curve is given. At the same time, the formula is generalized to the general situation, and the compound hollow steel pipe concrete with the index of deflection in the column is established.
【学位授予单位】：长安大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU398.9
本文编号：2508865
[Abstract]:With the continuous development of the national economy, the probability of explosion caused by the improper stacking of the gas and the combustible and explosive products and the aging of the electric appliance gradually increases, so that the possibility of the building structure being impacted by the explosion is increased. At the same time, the threat of the explosion to the construction structure is increasing as a result of the terrorist attacks worldwide. The structure has a good anti-explosion performance under the action of an explosion impact load, so that the structure is avoided, and the anti-explosion property of the column itself can play a very important role. The composite hollow steel tube concrete column has the characteristics of high bearing capacity, good plasticity and high bending rigidity, and is widely used as an important force component in the engineering structure. Therefore, it is of great theoretical significance and application value to study the explosion impact failure effect of compound hollow steel tube concrete column, and then to set up its damage evaluation method. In this paper, the dynamic response and damage assessment of the composite hollow steel tube concrete column under the explosion load are systematically studied by means of the experimental research and the numerical simulation method, which is of great theoretical significance and engineering application value. The main research work and innovative outcomes include the following aspects: (1) The numerical simulation of the interaction between the blast shock wave and the composite hollow steel pipe concrete column is studied. Methods: Based on the explicit dynamic program ANSYS/ LS-DYNA, the finite element numerical model of the steel tube concrete column, air and explosive under the explosion load of the ground reflection is established by the loading mode of the ALE flow-solid coupling, and the numerical simulation results of the air finite element mesh are further studied. The results show that the size of the mesh has a great effect on the wave and the propagation time of the shock wave. The peak of the shock wave pressure decreases with the increase of the grid size, and the higher the grid density, the higher the peak value of the shock wave and the peak pressure of the test. approach; (2) design of two steel-filled steel pipe concrete Through the analysis of the pressure of the measuring point and the macro-deformation of the column, the results show that under the action of the explosion load of the first test condition with the folding distance of 1.1 m/ kg1/3, the deformation of the column belongs to the elastic deformation, no plastic deformation is generated, and the column is still good The load-bearing capacity of the composite hollow-steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled concrete column has obvious plastic deformation under the action of explosion loading with a folding distance of 0.14m/ kg@@ The column is bent and deformed. The surface of the upper edge of the column bottom rib of the column-facing surface of the column is provided with a fine cross-section. The results show that the strength of the end node of the column and the overall strength of the component can be used to improve the anti-explosion of the composite hollow concrete column. The interaction between the explosion shock wave and the structural column and its action on the column are studied in (3). Through the analysis of the parameters, the results show that the increase of the hollow rate can reduce the pressure of the concrete in the core region of the column, so as to improve the anti-explosion performance of the composite hollow steel tube concrete column to a certain extent, even if the action time of the positive pressure is consistent, the pressure generated by the circular section The value is also lower than that of the square section, so the anti-explosion property of the circular section is superior to that of the square section, and the strength grade of the concrete is improved, the impact resistance of the composite hollow steel tube concrete column can not be greatly influenced, and the change of the folding distance on the dynamic response and the resistance of the compound hollow steel tube concrete column The rate of increase of the displacement peak of the column to the detonation surface increases rapidly with the reduction of the folding distance, the rate of increase of the pressure peak is much larger than the reduction rate of the folding distance, the more the folding distance is, the pressure of the column to the detonation surface The more sensitive the change is, (4) the deformation of the bending deflection in the concrete column based on the compound hollow steel pipe is established. Based on a large number of numerical simulation tests, this paper establishes the compound hollow steel pipe concrete column damage based on this paper. Class boundary, that is, the P-I curve. The mathematical expression of P-I curve is given. At the same time, the formula is generalized to the general situation, and the compound hollow steel pipe concrete with the index of deflection in the column is established.
【学位授予单位】：长安大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU398.9
【引证文献】
相关博士学位论文 前3条
1 都浩;城市环境中建筑爆炸荷载模拟及钢筋混凝土构件抗爆性能分析[D];天津大学;2009年
2 师燕超;爆炸荷载作用下钢筋混凝土结构的动态响应行为与损伤破坏机理[D];天津大学;2009年
3 李天华;爆炸荷载下钢筋混凝土板的动态响应及损伤评估[D];长安大学;2012年
本文编号：2508865
本文链接：https://www.wllwen.com/kejilunwen/sgjslw/2508865.html
