Lining Technology of Saturated Sand Layer Underground Diversion Tunnel and the Measurement of Concrete Lining Thickness

In order to improve the construction technology quality of the diversion tunnel lining in saturated sand stratum, the lining technology of underground diversion tunnel in saturated sand stratum is studied in detail in this paper. Steel trolley is used to complete binding production, and HBT-20 concrete pump is used to transport concrete. Concrete construction starts from bottom plate and side arch. After the construction, the quality of the diversion tunnel lining is tested nondestructively by the impact elastic wave, and the thickness and defects of the lining are analyzed by the reflection characteristics and spectral relationship of the impact elastic wave. The strength of lining concrete is measured by the propagation characteristics of R wave and the relationship between wave velocity and strength. The results show that the maximum additional bending strain of tunnel wall is about 300 με. At measuring point B7, the thickness and strength of concrete lining can be accurately measured by nondestructive quality testing technology.