RESEARCH PROGRESS ON CRACKING AND MECHANICAL BEHAVIOR OF LINING DURING DOUBLE-ARCH TUNNEL CONSTRUCTION

Double-arch tunnels are widely used in engineering because of the high space usage. Cracking is frequently observed in the first tunnel lining during construction of the second tunnel. To study the cracking and mechanical behavior of the lining in this process, an analysis method including distributed optical-fibre monitoring, inversion analysis method and finite element simulation that can reflect concrete cracking is proposed in this paper. Domestic and foreign literatures are extensively investigated, and the relevant research results of the authors are summarized, including: based on the actual engineering case, the application of distributed optical-fibre monitoring in the double-arch tunnel construction is realized. A more accurate inversion analysis method of mechanical behavior of tunnel linings is proposed. The feasibility of using the total strain rotating crack constitutive model to reflect the mechanical properties and cracking modes of reinforced concrete components subjected to complex stress and confinement is verified. The research methods and conclusions in the paper can provide a reference for related engineering practice.