Mechanical characteristics and optimum execution of pre-support system in mountain tunneling method

为了弄清管棚支架对山区隧道掘进法中隧道工作面开挖引起的地表沉降量的定量影响，进行了数值分析、离心模型试验和现场调查，分析中考虑了对工作面稳定性影响较大的隧道工作面开挖过程。通过接触单元法的数值分析，明确了管棚对稳定工作面和减小地表沉降量的作用。研制了一种开挖机器人，并将其应用于离心式模型试验。该机器人由程序进行三维控制，可以挖掘任意形状的隧道工作面。明确了全断面开挖和环切开挖等开挖方法的不同对地表位移的影响。

In order to make clear the quantitative effects of pipe roof supports on the decrease of the ground settlements caused by tunnel face excavations in mountain tunneling method, numerical analyses, centrifugal model tests and field investigations have been conducted.The excavation process of the tunnel face, which gives big influence on the face stability, is taken into account in the analysis. The effects of the pipe roof to stabilize the face and to decrease the settlements of the ground surface are made clear through numerical analysis of CEM(Contact Element Method).An excavation robot is newly developed and is applied to the centrifugal model tests. The robot is three-dimensionally controlled by programs and can excavate the tunnel face in arbitrary shape. Effects of the difference between the excavation methods such as the full-face-excavation and the ring-cut-excavation on the ground displacements are made clear.