Disclosed are methods, compositions, and composition packages for spray-coating a membrane for waterproofing a concrete tunnel applications. After primer coating is applied onto a surface in the tunnel, the coating composition is sprayed to form a membrane, and then concrete is cast or sprayed against the membrane so that it can bond to the membrane. Coating compositions comprise two or more acrylate monomers, as well as initiator, accelerator, and optional additive. Preferably, the coating composition is established by using a two-part package, one part having initiator, the other part having accelerator, and each part containing the monomers and optional additives so that the two parts can be shipped to the application site and mixed in a 1:1 ratio during spraying. The waterproofing coating composition provides excellent bonding with concrete.