Development and application of a long face reinforcing method with GFRP tubes in mountain tunneling

摘要

The long face reinforcement with GFRP tube, forms an improved ground core ahead of the face. This method uses a double-tube drilling system. Glass fiber reinforced tubes are driven into the face, which serve as casings, and a polyurethane or a cement agent are injected through the tubes. It not only stabilizes the tunnel face, it also prevents loosening ahead of the face. This paper discusses the development of the FIT method and its application to tunneling projects. In addition, its effectiveness is verified on the basis of the measurements and identification analysis results by the finite difference method.