At the region of tunnel collapse where karst developed,it is important to select appropri-ate construction scheme.The section ZK67 +390 ~ZK67 +270 of left tunnel from Shanjiawan tunnel exit were predicted by using the Tunnel Seismic Prediction.It is deciphered that there may be filling cavity near ZK67 +360.The filling cavity was uncovered and collapse occurred when the drift reached ZK67 +360.The predict results are generally in good agreement with the field-observed results.Based on an engi-neering case,the advantages and disadvantages of various treatment programs were analyzed,the optimal solution to treat the collapse is given:protective arch technique combining mortar anchor which was strengthened rock surface of collapse cavity.In order to test consolidation effect,observational method of consolidated tunnel collapse zone was constructed;convergence displacement and vault crown settlement were measured.It is shown from measured results,this method is the optimization method for temporary support requirements against potential collapse.%对于岩溶区隧道塌方地段，选取合理的处治方案是非常关键的。利用 TSP 超前地质系统对尚家湾隧道出口左洞 ZK 67＋390～ZK 67＋270进行了探测，破译出 ZK67＋360附近可能赋存充填型溶腔，当施工至 ZK67＋360时充填型溶腔揭露并发生塌方，探测结果与现场实际揭露情况基本吻合。根据工程塌方处治实例，比较分析各种塌方处治方案的优缺点，给出了优化处治方案：护拱法配合砂浆锚杆稳固塌腔岩面。在处理段增设监测断面，通过监测隧道的水平收敛位移和拱顶沉降量以及钢拱架的内力反映隧道围岩的稳定状况，量测结果表明，在一定时间内围岩达到稳定，表明采用此方法处理隧道塌方区效果良好。
展开▼
