万家寨引黄工程南干７＃隧洞进口段穿过忻保公路、宁岢铁路和正在施工的神朔铁路隧道。地质情况与土石过渡段，有黄土状亚沙土、黄土状亚粘土、Ｎ２红粘土、白云质灰岩、豹皮状灰岩，严重风化破碎。施工中采用上下台级法、超前锚杆法，三至四次循环开挖、钢拱架支护和一次衬砌，混凝土浇筑中防渗止水带定位，施工过程中加强观测预报，顺利完成这一艰难段的施工任务。 Wanjiazhai Yellow River Diversion Project Nangang 7 # tunnel entrance through Xin Bao Road, Ninglang Railway and the construction of the Shen-Shuo railway tunnel. Geological conditions and the transitional section of earth and stone, with loess-shaped sandy soil, loess-like clay, N2 red clay, dolomitic limestone, leopard skin limestone, severe weathered broken. During the construction, the method of up and down stairs, advanced bolt method, excavation of three to four cycles, support and lining of steel arch support and anti-seepage stoppage of water in concrete pouring are adopted to enhance the observation and forecast during the construction and smooth completion of this A difficult section of the construction task.