Simplified Dynamic Calculations of Internally Loaded Lined Tunnels, in Rock

摘要

Preliminary calculations of steel lined cylindrical tunnels under internal pulses were performed with the TD code. The code was obtained from the US Army Engineer Waterways Experiment Station, and was modified and enhanced for our purpose. The most conspicuous results of these calculations were: the large reduction in liner hoop stress provided by backing up the liner against a competent rock; and the ability to keep the liner in the elastic range of behavior by locating the tunnel in a hard rock such as competent granite. The matter of properly anchoring the liner to the surrounding rock with fully grouted bolts or tendons also was addressed. This minimizes the movements of the liner/rock interface upon the rebound phase of loading. This report also outlines recommended future work. (ERA citation 08:010818)