沙特NEOM隧道项目地震波法超前地质预报技术

Application of Tunnel Seismic Prediction in Geological Prediction in Saudi Arabia NEOM Tunnel Project

沙特NEOM隧道项目采用钻爆法施工,采用超前水平钻探法进行地质预报。该项目工期要求非常紧张,如何优化施工工序、缩短每循环时间,是项目面临的一大挑战。隧道采用三臂台车超前钻孔时,钻进速度慢,容易出现跑钻、卡钻现象。为了进一步缩短时间,提高超前地质预报质量,经比选,最终考虑采用地震波法替代超前水平钻探法,缩短超前钻孔在每循中占用的时间约0.5h。同时,通过对地质素描、超前水平钻孔及地震波法预报结果进行对比分析,证明了采用地震波法超前地质预报方案可行。采用超前水平钻探法、地震波法相结合的预报方法,辅以地表地质调查、洞内地质素描,能够极大提高隧道内不良地质的分布及地下水的预测精度。

NEOM tunnel project in Saudi Arabia was constructed by drilling and blasting method and probe holes were requested for geological prediction.The construction programme of this project was very tight.The major challenge for the project was how to optimize the construction sequence and reduce the cycle time.Drilling speed of the jumbo machine was very slow,falling off of drill string and drill rod stuck happened occasionally.In order to further shorten the drilling time and guarantee the quality of advance geological prediction,the tunnel seismic prediction method(TSP)was used to replace the probe holes after comparison and discussion,and the duration of each geological prediction was reduced by 0.5 hours per cycle.At the same time,through the comparative analysis of prediction results from geological mapping,horizontal drilling and TSP,it is proved that TSP method is feasible,the prediction method combined with advanced horizontal drilling,ground survey and mapping during excavation can greatly improve the prediction accuracy of the distribution of poor geological and groundwater in the tunnel.