Abstract: According to the principle of measuring the broken rock zone(BRZ) with GPR, the method of the measuring of the broken rock zone was proposed. According to the measuring of Gonghe-tunnel, the law of the distribution and vary of broken rock zone of unsymmetrical-tunnel in geologic were obtained. Based on the law of failure of layered rock and the theory of slab-rent structure, the failure model of the rock of unsymmetrical-tunnel in geologic and the reason of the failure of liner were worked out and the treating measurement was proposed.