Insulated tunnel liner and rehabilitation system

Abstract

An insulating and rehabilitation system especially adapted to unlined rock tunnels for the prevention of ice buildup on tunnel arches, walls and base structure the prevention of future deterioration of tunnel rock structure resulting from freeze-thaw cycle, and the stabilization of present tunnel rock structure which has been weakened by prior freeze-thaw cycles. The system comprises a modular system of sandwich panels with protected metal skins and insulating cores, prefabricated as a complete liner system to conform with tunnel dimensions and clearance requirements. The insulating liner system is designed to provide sandwich panel construction for high section modulus, flexural strength and minimum panel thickness, minimization of rock bolt support system, discontinuous metal hangars to eliminate thermal transfer, modular construction with cam-lock joints to minimize field labor and accommodate construction under live-traffic conditions, joint design to accommodate thermal expansion and contraction, waterproof construction to preclude freeze-thaw cycle deterioration, low thermal conductivity to accommodate extreme lows of temperature, noncombustibility, and reasonable installed cost. Under appropriate circumstances where the rock structure of the tunnel has deteriorated to the extent that rehabilitation of the rock face of the tunnel is required, the void between the rockface and the liner is filled with a lightweight, chemically hardening structural material to maintain the present position of key rocks in tunnel arches and walls, and to preclude further deterioration from freeze-thaw cycles.

Dependencies are inferred from the claim text.