COMPARISON TESTS OF CRACK CONTROL METHODS ON TUNNEL CONCRETE LINING MODEL

Abstract

The purpose of this research is to examine control methods of cracks caused by drying shrinkage of tunnel concrete lining. Curing conditions, materials, and restrain conditions were compared for the grade of cracks by model tests, which simulated tunnel concrete lining. Consequently, it was revealed that spray curing and expansive additive were effective as a curing condition and a material, respectively, and the reduction effect of restrain was large by laying waterproof sheets. Moreover, the restrain condition at the back of the concrete lining of an actual tunnel was verified by the stress analysis using 2-D FEM.