Water Infiltration and Crack Control for Tunnel Concrete Lining
Cracking in tunnel linings is a major cause for reduction in serviceability due to water infiltration and exfiltration, and reinforcement corrosion. In current industry practice, in order to control ground water inflow in lined tunnels, maximum crack width is limited to allowable values in a range of 0.15-0.3 mm specified by the codes, guidelines and recommendations. However, a correlation between allowable crack width and corresponding water inflow in tunnel has not been provided. This paper presents an analytical methodology for prediction of initial water inflow into tunnel concrete linings and provides formulas that are sensitive to factors such as lining geometry, temperature, reinforcement type, and ground water pressure head.