摘要
在通过化学爆炸模拟核爆炸加载的缩尺结构抗爆试验中,为使结构变形满足几何相似,需设计约束和封闭等特殊方案来提高化学爆炸荷载作用时间,显著增加了缩尺结构试验的成本和难度,且缩尺比例越小,误差越大。为解决该问题,提出一种爆炸荷载作用下钢梁动力响应的相似分析方法,并通过数值计算验证了该方法的准确性。结果表明:在弹性响应阶段,若要使钢梁跨中最大变形满足几何相似,则需要模型与原型材料相同且几何形状相似,化学爆炸加载模型与核爆炸加载原型结构的等效静载相同;在塑性响应阶段,钢梁跨中最大变形无法满足几何相似,仅在缩尺模型化学爆炸荷载持时长于一最小作用时间的情况下,可通过几何相似系数与延性比系数的乘积来表示模型和原型的变形相似关系,并给出了延性比系数的解析表达式。
During the testing of scaled models to simulate a nuclear explosion using a chemical explosion,it is necessary to implement specific measures such as restraint and sealing to prolong the duration of the chemical explosion.Although these measures ensure geometric similarity in structural deformation,they also amplify the testing costs and complexities,particularly when scaling down the model,resulting in significant inaccuracies.To address this limitation,this paper proposes a novel method for similarity analysis of the dynamic response of steel beams under blast loading.The proposed method's accuracy was validated through numerical calculations,revealing that geometric similarity can be maintained during the elastic response stage,subject to certain conditions,including the use of the same material for both the scaled model and the prototype,similarity in geometric shape,and equivalence of the equivalent static load between the chemical explosion model and the prototype structure.However,the maximum mid-span displacement fails to satisfy geometric similarity during the plastic response stage.Under the condition that the duration of the scaled model's explosion load is longer than the minimum action time,the similarity relationship between the model and the prototype can be expressed as the product of the geometric similarity coefficient and the ductility ratio coefficient,with the analytical expression for the latter provided.
作者
刘思嘉
陈力
冯彬
LIU Sijia;CHEN Li;FENG Bin(Engineering Research Centre of Safety and Protection of Explosion&Impact of Ministry of Education,Southeast University,Nanjing 211189,China;State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510640,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2024年第1期27-35,共9页
Journal of Building Structures
基金
国家自然科学基金项目(51978166)
华南理工大学亚热带建筑科学国家重点实验室开放基金(2020ZA02)。
关键词
钢梁
爆炸荷载
相似分析
动力响应
等效静载
延性比系数
steel beam
blast load
similarity analysis
dynamic response
equivalent static load
ductility ratio coefficient
