Analysis of Monitoring and Measurement of Small Clear Spacing Tunnel in the Excavation by NATM

Due to its convenience, quickness, cheapness and so on, NATM is widely used in the tunnel excavation. In order to guarantee security when tunnel construction and study the stability of tunnel surrounding rock, Supervision and measurement is essential in the tunnel excavation, the result of which may influence tunnel excavation directly. Based on the analyses of measured data, the distribution characteristics and variation laws of the ground settlement, crown settlement and convergence around the tunnel, the displacement of the interior of surrounding rock are all studied. The study results are drawn to provide the basis for modifying and optimizing the design and construction scheme.