Weld-Crete®, the original chemical bonding agent for concrete, is a safe, easy to use surface applied bonding agent that bonds new concrete to any clean, structurally sound surface. It has been specified and used by major architects, engineers and construction companies throughout the world since 1952. Weld-Crete® is applied as a liquid and as it dries to a thin, flexible film, it forms a tenacious bond to the structural surface. The dry film is reactivated by the moisture and chemical reaction that occurs as the new concrete cures. Full bonding strength is achieved after the new concrete has completely cured.