TBM与钻爆法在并行长大引水隧洞施工中的适用性研究

Applicability Study on TBM and Drilling-blasting Method for Construction of Parallel Long and Large Diversion Tunnels

在某水电站并行长大引水隧洞中,通过对隧洞规模、沿线工程地质条件、施工工期及开挖渣料再利用等进行综合对比分析,研究钻爆法与TBM施工方法的适用性。TBM施工方法在难以增加施工支洞的长隧洞工程中具有较明显优势,而钻爆法在大断面、复杂地质条件隧洞开挖施工中的适用性更强。通过布置合适的施工支洞,可有效增加该引水隧洞施工断面,从而加快钻爆法施工进度,而TBM施工出渣料粒径过小,难以满足洞渣作为骨料再利用的要求,且引水隧洞开挖洞径大,所在区域地质条件复杂,缺少相关工程参考经验,一旦突发施工事故,难以快速解决,工期不确定性增加,因此推荐采用钻爆法作为该水电站并行长大引水隧洞的主要开挖方式。

Taking the parallel long diversion tunnel of a hydropower station as an example, the applicability, of drilling and blasting method and TBM construction method, is studied by comprehensive comparative analysis of tunnel size, engineering geological conditions along the line, construction period and excavation slag reuse, etc. TBM construction method has obvious advantages in the construction of long tunnel projects, which are difficult to increase the construction adits;while drilling and blasting method has stronger applicability in the construction of tunnel excavation projects with large section and complex geological conditions. By arranging appropriate construction adits, the construction section of the diversion tunnel can be effectively increased to speed up the construction progress with drilling and blasting method. However, the particle size of the slag produced by TBM construction is too small to meet the requirements of the reuse of the slag as aggregate. In addition, due to the large diameter of the diversion tunnel excavation, complex regional geological conditions, and the lack of relevant engineering reference experience, once a construction accident occurs, it is difficult to quickly solve, thus increasing the uncertainty of the construction period. Therefore, drilling and blasting method is recommended as the main construction excavation method of the parallel large diversion tunnel of the hydropower station.