单层球面网壳基于GBS系统外爆试验及响应分析

发布时间：2018-06-04 08:08

本文选题：单层球面网壳 + 外爆　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：社会的进步使大跨空间结构得到长足的发展,空间网壳结构作为其代表性形式得到广泛应用。但近年来爆炸恐怖袭击活动日益猖獗,大跨空间结构因其人口密度大、社会影响大和抗爆措施薄弱等特点而容易成为恐怖袭击的目标。因此,开展对大跨空间结构的抗爆性能研究具有重要的理论意义和应用价值。GBS系统是以乙炔/空气混合气体为爆炸物的爆炸模拟试验装置,拥有独立隔离的爆炸装置和控制平台,具有操作简便和安全的特点;AUTODYN是嵌于ANSYS下的显式分析工具,拥有完备的材料库和完善的流固耦合算法,其独特的REMAP技术可以精确计算爆炸荷载。本文针对目前大跨空间结构爆炸试验缺乏的问题,以GBS系统为试验环境,设计制作了K6单层球面网壳缩尺模型,开展外爆试验,研究网壳在外爆荷载下的响应规律;使用AUTODYN对网壳模型和试验环境进行建模,开展关于网壳外爆的数值模拟,数值再现试验过程,并与试验结果进行对比分析,探讨模拟方法的适用性。试验准备阶段进行了网壳模型构件的材性试验,获得了相应的材料力学性能参数;同时进行网壳模态测试,验证了网壳的制作加工精度。结合模拟分析和试验设备条件开展外爆试验,分析总结了网壳结构随外爆荷载增加的响应趋势,依次划分出无损伤、轻微损伤、中等损伤、严重损伤和整体倒塌等五种响应模式。选取已经获得轻微损伤模式的网壳模型,对其开展二次外爆荷载响应试验,得到其响应规律,考察了累积损伤对网壳结构的危害。数值模拟基于爆能等效原理,将试验气体等效转化为TNT进行计算。将模拟结果与试验结果进行宏观响应趋势以及测试数据两方面对比,证明了等效TNT方法能够合理描述网壳在外爆试验时的最大响应,适用于简化分析试验问题。结合试验数据修正了等效TNT方法的折减系数,并通过模拟轻微损伤状态网壳模型的二次外爆试验,验证了修正方法的准确性。本文尝试提出了模拟试验环境的气体模拟法,讨论了其模拟结果的合理性和适用性,并对后续试验方法和模拟方法的完善提出了若干建议。
[Abstract]:With the progress of society, the large span space structure has been developed rapidly, and the space reticulated shell structure has been widely used as its representative form. However, in recent years, the explosive terrorist attacks are increasingly rampant. Because of its large population density, social impact and weak anti-explosion measures, the long-span space structure is easy to be the target of terrorist attacks. Therefore, it is of great theoretical significance and practical value to study the anti-explosion performance of long-span space structures. GBS system is an explosive simulation test device with acetylene / air mixture gas as explosive. With an independently isolated explosive device and control platform, with the characteristics of simple and safe operation, AUTODYN is an explicit analysis tool embedded in ANSYS, with a complete material library and a perfect fluid-solid coupling algorithm. Its unique REMAP technique can accurately calculate the explosion load. In this paper, aiming at the lack of explosion test of large span space structure at present, taking GBS system as the test environment, the paper designs and makes the scale model of K6 single-layer spherical reticulated shell, carries out the external explosion test, and studies the response law of the latticed shell under the external explosion load. Using AUTODYN to model the latticed shell model and test environment, the numerical simulation of the shell explosion was carried out, and the experimental process was numerically reproduced. The simulation results were compared with the test results and the applicability of the simulation method was discussed. The material properties of latticed shell model members were tested in the preparation phase of the test, and the corresponding mechanical properties of materials were obtained. At the same time, the modal test of the reticulated shell was carried out to verify the machining accuracy of the reticulated shell. Combined with simulation analysis and test equipment condition, the response trend of reticulated shell structure with the increase of external blasting load is analyzed and summarized, and the non-damage, slight damage and moderate damage are divided in turn. There are five kinds of response modes, such as severe damage and whole collapse. In this paper, the model of reticulated shell with slight damage mode has been selected, and the response law of the latticed shell has been obtained by carrying out the secondary explosive load response test, and the damage of accumulated damage to the latticed shell structure has been investigated. Based on the principle of explosive energy equivalence, the experimental gas is transformed into TNT to calculate the numerical simulation. By comparing the simulation results with the experimental results, it is proved that the equivalent TNT method can reasonably describe the maximum response of the latticed shell under external explosion test, and is suitable for simplified analysis of test problems. The reduction coefficient of the equivalent TNT method is corrected with the experimental data and the accuracy of the modified method is verified by simulating the secondary explosion test of the reticulated shell model with slight damage. This paper attempts to put forward a gas simulation method for simulating the test environment, discusses the rationality and applicability of the simulation results, and puts forward some suggestions for the improvement of the subsequent test methods and simulation methods.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU399

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