To study the anti-explosion protection effect of polyurea coating on reinforced concrete box girder,two segmental girder specimens were made at a scale of 1:3,numbered as G(without polyurea coating)and PCG(with polyur...To study the anti-explosion protection effect of polyurea coating on reinforced concrete box girder,two segmental girder specimens were made at a scale of 1:3,numbered as G(without polyurea coating)and PCG(with polyurea coating).The failure characteristics and dynamic responses of the specimens were compared through conducting explosion tests.The reliability of the numerical simulation using LS-DYNA software was verified by the test results.The effects of different scaled distances,reinforcement ratios,concrete strengths,coating thicknesses and ranges of polyurea were studied.The results show that the polyurea coating can effectively enhance the anti-explosion performance of the girder.The top plate of middle chamber in specimen G forms an elliptical penetrating hole,while that in specimen PCG only shows a very slight local dent.The peak vertical displacement and residual displacement of PCG decrease by 74.8% and 73.7%,respectively,compared with those of specimen G.For the TNT explosion with small equivalent,the polyurea coating has a more significant protective effect on reducing the size of fracture.With the increase of TNT equivalent,the protective effect of polyurea on reducing girder displacement becomes more significant.The optimal reinforcement ratio,concrete strength,thickness and range of polyurea coating were also drawn.展开更多
为研究爆炸荷载作用下涂覆聚脲混凝土自锚式悬索桥主梁的抗爆防护效果,以山东湖南路大桥为背景,通过试验和数值模拟结合的方法对自锚式悬索桥主梁的爆炸破坏特征和动力响应进行研究。采用2发3 kg TNT和1发5 kg TNT药柱,开展1∶3缩尺节...为研究爆炸荷载作用下涂覆聚脲混凝土自锚式悬索桥主梁的抗爆防护效果,以山东湖南路大桥为背景,通过试验和数值模拟结合的方法对自锚式悬索桥主梁的爆炸破坏特征和动力响应进行研究。采用2发3 kg TNT和1发5 kg TNT药柱,开展1∶3缩尺节段箱梁试件的2发单次爆炸试验和1发重复爆炸试验,分别编号为G(未涂覆聚脲箱梁)、PCG(涂覆聚脲箱梁首次起爆)、PCGR(涂覆聚脲箱梁二次起爆),试件顶面涂覆聚脲厚度为1.5 mm。通过LS-DYNA软件进行试件爆炸响应数值模拟及验证。研究结果表明,聚脲涂层可有效增强混凝土箱梁的抗爆性能,3 kg TNT在中间箱室上方0.4 m处首次起爆时,试件G中间箱室顶板形成贯穿性椭圆形破洞;试件PCG中间箱室顶板未贯穿,仅发生轻微的局部凹陷;5 kg TNT二次起爆后,试件PCGR中间箱室顶板出现近似圆形贯穿性破洞,1号和3号箱室在支撑处出现明显裂缝。涂覆聚脲后自锚式悬索桥主梁抗爆性能得到至少20%的提升,300 kg、500 kg、800 kg、1000 kg TNT当量作用下,未涂覆聚脲主梁顶板混凝土均出现贯穿性破洞;涂覆聚脲后仅在TNT当量为1000 kg时发生轻微贯穿。展开更多
基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20200494)China Postdoctoral Science Foundation(Grant No.2021M701725)+3 种基金Jiangsu Postdoctoral Research Funding Program(Grant No.2021K522C)Fundamental Research Funds for the Central Universities(Grant No.30919011246)National Natural Science Foundation of China(Grant No.52278188)Natural Science Foundation of Jiangsu Province(Grant No.BK20211196)。
文摘To study the anti-explosion protection effect of polyurea coating on reinforced concrete box girder,two segmental girder specimens were made at a scale of 1:3,numbered as G(without polyurea coating)and PCG(with polyurea coating).The failure characteristics and dynamic responses of the specimens were compared through conducting explosion tests.The reliability of the numerical simulation using LS-DYNA software was verified by the test results.The effects of different scaled distances,reinforcement ratios,concrete strengths,coating thicknesses and ranges of polyurea were studied.The results show that the polyurea coating can effectively enhance the anti-explosion performance of the girder.The top plate of middle chamber in specimen G forms an elliptical penetrating hole,while that in specimen PCG only shows a very slight local dent.The peak vertical displacement and residual displacement of PCG decrease by 74.8% and 73.7%,respectively,compared with those of specimen G.For the TNT explosion with small equivalent,the polyurea coating has a more significant protective effect on reducing the size of fracture.With the increase of TNT equivalent,the protective effect of polyurea on reducing girder displacement becomes more significant.The optimal reinforcement ratio,concrete strength,thickness and range of polyurea coating were also drawn.
文摘为研究爆炸荷载作用下涂覆聚脲混凝土自锚式悬索桥主梁的抗爆防护效果,以山东湖南路大桥为背景,通过试验和数值模拟结合的方法对自锚式悬索桥主梁的爆炸破坏特征和动力响应进行研究。采用2发3 kg TNT和1发5 kg TNT药柱,开展1∶3缩尺节段箱梁试件的2发单次爆炸试验和1发重复爆炸试验,分别编号为G(未涂覆聚脲箱梁)、PCG(涂覆聚脲箱梁首次起爆)、PCGR(涂覆聚脲箱梁二次起爆),试件顶面涂覆聚脲厚度为1.5 mm。通过LS-DYNA软件进行试件爆炸响应数值模拟及验证。研究结果表明,聚脲涂层可有效增强混凝土箱梁的抗爆性能,3 kg TNT在中间箱室上方0.4 m处首次起爆时,试件G中间箱室顶板形成贯穿性椭圆形破洞;试件PCG中间箱室顶板未贯穿,仅发生轻微的局部凹陷;5 kg TNT二次起爆后,试件PCGR中间箱室顶板出现近似圆形贯穿性破洞,1号和3号箱室在支撑处出现明显裂缝。涂覆聚脲后自锚式悬索桥主梁抗爆性能得到至少20%的提升,300 kg、500 kg、800 kg、1000 kg TNT当量作用下,未涂覆聚脲主梁顶板混凝土均出现贯穿性破洞;涂覆聚脲后仅在TNT当量为1000 kg时发生轻微贯穿。
