Control Water Leaks in Cracked Concrete Using Epoxy Grout

The objective of the testing program, approved by the EPA was to evaluate the performance of grouting materials used in the rehabilitation of cracked concrete structures, including pipes, to quantify the infiltration using a combination of model and laboratory tests at the Center for Innovative Grouting Materials and Technology (CIGMAT). A combination of grout and grout-substrate bonding with a simulated model test are being used to evaluate grouts for leak control at repaired cracks in concrete. The concrete crack repairs were simulated using concrete rings placed at selected distance apart and the grouted cracks were tested to 34 kPa (5 psi) water pressure, after subjecting the repaired joints to wet-dry cycles, to quantify the effective reduction in water infiltration. In this study, a commercially available epoxy grout was investigated based on a test protocol developed for EPA to evaluate the performance of grouts to control leak in cracked concrete. The average compressive strength, failure stain, and initial modulus after 3 days of curing were 45 MPa, 8%, and 1.5 GPa, respectively. After 6 months of wet-dry cycle test, the average bonding strength was 1.6 MPa. Model tests showed that the epoxy grout investigated in this study was effective in eliminating the leak in the cracked concrete immediately after grouting and after two wet and dry cycles over period of one month.