【作者】 樊海青；

【导师】 高建岭； 白玉星；

【作者基本信息】 北方工业大学 ， 结构工程， 2009， 硕士

【摘要】 爆炸产生的爆炸冲击波初值高、衰减快、持续时间短,但是对结构的破坏性大,因此研究结构在爆炸冲击波作用下的塑性极限具有重要的应用价值。本文对国内外抗爆设计方法进行了广泛的文献调研,针对爆炸冲击波荷载的特点,同时依据塑性极限理论提出了一种多层多跨框架结构抗爆分析方法——塑性极限方法。该方法以寻找多层多跨框架结构的塑性极限荷载(采用增量变刚度法求解)、塑性极限状态时的应力(或内力)分布和所形成的破坏机构为目的。本研究主要内容有:(1)依据爆炸冲击波基本理论,确定了爆炸冲击波的峰值超压△P_m的计算公式。(2)对爆炸冲击波动力特性进行了数值模拟,将冲击波超压△P_m转化为结点动荷载P_m的形式,然后利用静力等效的方法将动荷载P_m等效为静力荷载P作用到框架结构。(3)采用塑性极限理论对多层多跨框架结构进行塑性极限分析,通过运用增量变刚度法求出多层多跨框架结构的极限荷载、塑性极限状态时的应力(或内力)分布和结构最终的破坏机构。(4)用Fortran95语言将上述方法编制成计算程序,并模拟算例进行分析,将程序计算结果与sap2000的计算结果比较和分析。(5)建立了多层多跨框架结构达到最终破坏机构与炸药量和爆炸距离之间的关系,以此确定了结构的防护距离。最后,在全面总结全文工作的基础上,提出本课题尚待深入研究的若干问题。更多还原

【Abstract】 Explosive blast resulting from explosion shares an high initial value,fast decay and short duration,but large destruction to constructions,so that studying structure’ s plastic limit under explosive blast has an important application value.This article conducted extensive literature research for domestic and foreign anti-explosive design methods,with aiming at the characteristics of blast loads,we bring forward a explosion-resistance analysis method for multistory multispan frame structure by using the plastic limit theory --- the plastic limit method.Its’ aim is to find the multistory multispan frame structure’s plastic limit load (using stiffness increment variation method),and the plastic limit state of stress(or internal force) distribution and the formation of collapse mechanism.In this study,the main part of the contents of the following:(1) In accordance with explosive blast basic theory,identified the calculation formula of the explosion shock wave overpressurevalue(△P_m ).(2) Carried out numerical simulation to dynamic characteristics of the blast,got the equivalent shock overpressure(△P_m ) into node loads(P_m ),then got the equivalent dead load (P)of dynamic load(P_m )by using dynamic equivalence theory and spreaded to multistory multispan frame structure.(3) Analyzed the multistory multispan frame structure’s plastic limits by using plastic limit theory,through using stiffness increment variation method,got ultimate load of plastic and the stress(or or internal force)and the final collapse mechanism.(4)Compiled the calculation procedures of the above-mentioned method by using Fortran 95 languages,done an analysis of simulated examples,then done comparison and analysis to the calculated results and the calculated results of sap2000.(5)Established the relationship between structures’ultimate collapse mechanism and explosive usage and explosive distance,then indentified the shelter distance of structure. In the end,the content of this paper has been summarized and some problems,which need further study,have been proposed.更多还原