The performance of pressure cells for sprayed concrete tunnel linings

The paper examines the factors that affect the performance of tangential cells embedded in shotcrete tunnel linings. New data, derived from field monitoring, numerical modelling, and calibration tests carried out to simulate the embedment and crimping processes, are presented. These suggest that although well-designed embedded total pressure cells will have cell action factors close to unity, they cannot be assumed to provide reasonable estimates of the stresses within sprayed concrete linings, unless the influences of installation effects, temperature changes, shrinkage and subsequent crimping can be taken into account.