Polymer Pavement Concrete for Arizona Study II.

摘要

The most important result of this investigation is the development of the addition of urea-formaldehyde combinations in the form of a monomer system to the mixing water of portland cement mortars and concretes. Although the addition of this system to concretes produced only negligible strength increases,experimental data indicated that several combinations of the same system with mortars produced compressive strength increases of 1500to 2500psi. It is not clear at this time why the urea-formaldehyde monomer system is effective in mortars and ineffective in concretes. Further investigation is needed to improve the effectiveness of this monomer system in concretes,too. The application of such a monomer system is advantageous from economical standpoint because this is the least expensive form of the urea-formaldehyde combinations,and because the technology of such monomer systems in mortars and concretes is simple. Several other directions were also investigated,such as the optimization of the basic urea-formaldehyde prepolymers,acidic urea-formaldehyde prepolymers,and several other chemical systems and commercially available polymers. Some of these systems did produce strength increases but these were not high enough.