设防爆层钢箱梁缩尺结构抗近场爆炸作用试验研究

为研究设防爆层钢箱梁抗近场爆炸作用效果,以53 g炸药当量、70 mm爆距为典型爆炸条件,开展了混凝土-单层/双层钢丝网板、5层/10层凯夫拉板及其组合为防爆层的钢箱梁缩尺结构近场爆炸试验研究。以塑性变形能为抗爆效果考查指标,8种试验工况结果表明:近场爆炸作用下无防护钢箱梁顶板会发生沿U型加劲肋的撕裂破坏及球冠状凹坑,且横隔板间距250 mm比间距150 mm的钢箱梁顶板破坏严重,变形能约高出60%;混凝土-双层钢丝网板较单层钢丝网板能降低钢箱梁顶板的变形能约2.2%;混凝土-双层钢丝网板与5层凯夫拉组合作为防爆层,顶板塑性变形能降低至无防护结构钢箱梁顶板的34.5%,混凝土-双层钢丝网板与10层凯夫拉组合作为防爆层,该数值约为32.7%。

Tests for near-field explosion resistance of steel box girder scale structure with anti-explosion layer

Here,to study near-field blast resistance effect of steel box girder with anti-blast layer,taking 53 g explosive equivalent and 70 mm blast distance as typical blast conditions,near-field blast tests were conducted for steel box girder scale structures with concrete single-layer/double-layer steel wire mesh plate,5-layer/10-layer Kevlar plate and their combinations taken as anti-blast layer.Taking plastic deformation energy as the evaluation index of anti-blast effect,Test results under 8 test working conditions showed that under action of near-field blast,tearing failure along U-shaped stiffener and spherical coronal pits can occur on top plate of unprotected steel box girder,and top plate damage of steel box girder with transverse diaphragm spacing of 250 mm is more serious than that with transverse diaphragm spacing of 150 mm,top plate’s deformation energy for the former is about 60%higher than that for the latter;compared with concrete single-layer steel wire mesh plate,concrete double-layer steel wire mesh plate can reduce the deformation energy of top plate of steel box girder by about 2.2%;the combination of concrete double-layer steel wire mesh plate and 5-layer Kevlar is used as anti-blast layer,the top plate deformation energy can be reduced to 34.5%of the top plate deformation energy of steel box girder without protective structure;the combination of concrete double-layer steel wire mesh plate and 10-layer Kevlar is used as anti-blast layer,the top plate deformation energy can be reduced to 32.7%of the top plate deformation energy of steel box girder without protective structure.