摘要
为探究水下爆炸荷载作用下钢筋混凝土拱的动力响应特性和破坏特征,制作了两个钢筋混凝土拱试件,并开展了水下爆炸试验。试验分为拱外爆炸和拱内爆炸两组,采用10 g乳化炸药,试验时爆源距结构面最小距离为10 cm(起爆点位于拱结构正上方和正下方),通过传感器记录爆炸试验中钢筋混凝土拱典型断面处的水压力及加速度时程曲线。基于Arbitrary Lagrange-Euler(ALE)算法,建立了空气-水-炸药-钢筋混凝土拱等多介质动态耦合作用模型,将数值模拟结果与试验结果对比,验证了数值方法的可靠性。采用验证后的数值模型进一步研究了拱外及拱内爆炸荷载作用下钢筋混凝土拱的动力响应差异。结果表明:相同炸药当量下,内部爆炸有更多的能量作用于混凝土拱,使结构的动力响应更强烈;外部爆炸下,拱顶、拱腰处产生较大裂缝;内部爆炸时,迎爆面裂缝数量明显增多,拱肩位置出现裂缝。钢筋混凝土拱形结构抵抗外部爆炸荷载的能力明显强于内部爆炸荷载。
As common structures in hydraulic engineering,the arch structures may suffer from explosion load during their operation life.In order to explore the dynamic response characteristics and failure features of reinforced concrete arches subjected to underwater explosions,two reinforced concrete arch specimens were fabricated and underwater explosion tests were carried out.The tests consisted of two groups:external explosion and internal explosion.10 g emulsion explosives were used,and the minimum distance between the explosion source and the structure was 10 cm(the explosives were placed directly above or below the arch).The time history curves of water pressure and structural acceleration at typical sections of the arches during the explosion tests were recorded.Based on the Arbitrary Lagrange-Euler(ALE)algorithm,a multi-material dynamic coupling model,including air,water,explosive,and reinforced concrete arch was established.The initiation of explosive,the propagation of shock wave,the interaction between fluid and solid,and the dynamic response of the structure were considered in the numerical model.The reliability of the numerical model was verified by comparing the numerical results and the experimental results.With the calibrated numerical model,the difference of dynamic response of reinforced concrete arches under external explosion and internal explosion was further studied.The results show that more energy acts on the concrete arch,and the structural response is stronger when subjected to internal explosion.Large cracks occur at the vault and waist induced by external explosion.Compared with the external explosion,the number of cracks significantly increases under internal explosion,and cracks also appear at the spandrel.The ability of reinforced concrete arch to resist external explosive loads is significantly stronger than that of internal explosive loads although the explosive weight is the same.For concrete arches that are vulnerable to external explosions,high strength concrete or reinforced reinforcement can be appropriately used in the arch vault and waist.For concrete arches that may be subjected to internal explosions,protective nets can be set to make the explosion occur at a longer distance away from the structures,or high strength materials can be used to resist the overall deformation.
作者
杨广栋
田许杰
范勇
田斌
卢晓春
YANG Guangdong;TIAN Xujie;FAN Yong;TIAN Bin;LU Xiaochun(Hubei Key Laboratory of Construction and Management in Hydropower Engineering,China Three Gorges University,Yichang 443002,Hubei,China;College of Hydraulic&Environmental Engineering,China Three Gorges University,Yichang 443002,Hubei,China)
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
2024年第2期37-52,共16页
Explosion and Shock Waves
基金
国家自然科学基金(52209162,52379128)
湖北省自然科学基金(2023AFA048,2023AFB657)
湖北省水电工程施工与管理重点实验室(三峡大学)开放基金(2023KSD04)
湖北省青年拔尖人才培养计划项目。
关键词
钢筋混凝土拱
拱外爆炸
拱内爆炸
水下爆炸
抗爆性能
reinforced concrete arch
external explosion
internal explosion
underwater explosion
blast resistance
