Development and Application of a Test System for Modeling Tunnel Excavation with Transparent Rock Surrogate

摘要

Physical modeling using transparent rock or soil surrogates and optical measurement is an effective way to obtaining the displacement and stresses within test specimens in geotechnical engineering. To apply the prospective modeling method to investigating the mechanism of excavation-induced failure of rock surrounding tunnels, a novel test system is developed for modeling tunnel excavation with transparent rock surrogate. The system includes three parts: one transparent acrylic chamber and its reinforcing units for containing scaled models, a dead-weight loading device consisting of levers and pulleys, and a three-dimension optical stressometer made of polyurethane block and fiber Bragg gratings. The test system is then employed to visualize the excavation of a round tunnel and some favorable results are gained. To some extent, the work in this article improves the physical modeling techniques and provides an effective method for the modeling research in rock tunnel engineering.