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Abstract Based on anti-explosion model test device，the anti-explosion capacity of underground openings，which are reinforced by rock bolts with end wave-decay by holes and reinforced by dense rock bolts，is studied under explosive stress waves produced by focus charging. By comparing anti-explosion capacities of three underground openings，the differences of vertical stresses，relative roof-to-floor displacements of three underground openings，surface strains of three underground openings，accelerations of roof and floor of three underground openings and damage shapes of three underground openings are analyzed. The results show that under explosive stress waves，the relative roof-to-floor displacements and maximum surface strains of underground openings are reduced without severe damage；and the acceleration of roof is also decreased to certain degree. It is also shown that the fractures of underground openings are distributed at both sides of arch foots，but the fractures on the arches of two underground openings are fewer；and their surrounding rocks are lightly damaged. These conditions indicate that the underground openings with end wave-decay by holes and reinforced by dense rock bolts can increase their anti-explosion capacities.
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Received: 09 April 2009
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