地下超高性能钢纤维混凝土隧道衬砌抗爆性能模拟研究

NUMERICAL SIMULATION OF BLAST-RESISTANT PERFORMANCE OF UNDERGROUND TUNNEL WITH ULTRA HIGH PERFORMANCE STEEL FIBER REINFORCED CONCRETE LINING

针对超高性能钢纤维混凝土（UHPSFRC）隧道衬砌的抗爆性能,运用有限元软件LS-DYNA建立了超高性能钢纤维混凝土隧道衬砌在内爆荷载作用下的三维有限元模型,比较了UHPSFRC隧道衬砌与普通混凝土隧道衬砌抗爆性能的异同,研究了爆源位置、隧道埋深、钢纤维掺量等参数对UHPSFRC隧道衬砌抗爆性能的影响。结果表明：与普通混凝土隧道衬砌相比,UHPSFRC隧道衬砌抗爆性能更为优异;偏心爆炸情况下隧道衬砌主要表现为局部破坏,并且局部破坏程度要明显大于中心爆炸情况;与深埋工况相比,浅埋隧道衬砌在爆炸荷载作用下的损伤破坏更为严重;在一定范围内钢纤维掺量越大,隧道衬砌抗爆性能越好。

In order to study the blast-resistant performance of underground tunnel with ultra high performance steel fiber reinforced concrete（ UHPSFRC） lining,a 3 D finite element model was developed to simulate the dynamic response of a buried UHPSFRC tunnel under internal blast load based on the material properties of UHPSFRC. The effects of main parameters,such as the location of explosive charge,burial depth and volume ratio of steel fibers on blast-resistant performance were investigated by the FEM model. The results indicated that compared with the underground tunnel with normal concrete lining,the underground tunnel with UHPSFRC lining had better blastresistant performance. The main failure mode of lining was local failure under eccentric explosion,and it was much more serious than that of the central explosion in the tunnel. Compared with the deep buried condition,the damage of the shallow buried tunnel lining was more serious under the blast load. The blast-resistant performance increased with the increase of volume ratio of steel fibers in a certain range.