Performance of spray-applied epoxy lining system subject to infiltration

• Sprayed-in repair technique for deteriorated concrete infrastructure subject to infiltration.
• Alternative technique to cured-in-place techniques.
• System resists over 2700 kPa hydrostatic infiltration forces.
• System resists over 800 kPa sustained hydrostatic infiltration force without creep.
• System mitigates effects of large flaws and may installed in wet conditions.

This study focuses on a bonded repair technique for deteriorated concrete infrastructure located below the water table. A spray-applied lining system is a monolithic system applied to the inside of a concrete structure, such as a pipe, culvert or tank, sealing the structure and mitigating limit states associated with structural deterioration, corrosion and/or infiltration. The resulting lining is a thin, durable, chemical resistant product that is intimately and permanently bonded to the host structure. An experimental program utilising hydrostatic pressure, intended to mimic hydrostatic forces driving infiltration into a cracked concrete pipe, was conducted. Parameters considered in the study include concrete flaw size, epoxy thickness and concrete surface preparation. Results indicate that the performance of the spray-applied epoxy system is governed primarily by host concrete tensile strength and epoxy shear capacity. The proposed system represents a feasible alternative for the repair of concrete infrastructure, including large diameter pipe, subject to large hydrostatic infiltration forces.