Disposal construction and technology discussion of high pressure water inflow in the extra long tunnel

Combining with the engineering example, introduces the main constucion techniques, such as advance geologic forecast, precaution way of high pressure water blow-out and the curtain grouting blocking, which are adopted to deal with the high pressure water blow-out in the extra long tunnel. The paper also analyzes and discusses the construction process of the tunnel in the zones rich in karst and water. The available construction project is put forward.