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Abstract In order to research whether the new composite anchorage type of structure can improve the blast-resisting behavior for rock cavities，comparative field blast-resisting tests of new composite anchorage type of structure and single anchorage type of structure have been carried out. It is shown that critical damage load of cavity of new composite anchorage type of structure is 143% against that of the single anchorage type of structure. For the damage extent，the cavity of single anchorage type of structure is 2.5 times larger than that of new composite one. Under the lower blast load，the value of the vibration acceleration of the single anchorage type of structure is 1.6 to 12.3 times larger than that of the new composite one. The average displacement of the new composite anchorage type of structure is 65% compared with that of the single one. The time stress wave time acting on new composite anchorage type of structure is 2.5 to 5.0 times larger than that of the single one. The maximum strain of single anchor bolts is 2 to 4 times and even 6.9 times larger than that of the new composite one. The maximum surface strain of single anchorage structure is 2 times larger than that of the new composite anchorage structure. The new composite anchorage type of structure has an obvious reducing effect. So it is feasible to adopt the new composite anchorage type of structure to reinforce the rock cavity，which has great technical and economic benefits.
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Received: 20 April 2009
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