A STUDY OF 4 WATERPROOFING SYSTEMS FOR CONCRETE

As part of a study of possible mitigatory measures for concrete structures damaged by alkali-aggregate reaction, four treatments for waterproofing concrete (two coatings and two pore liner penetrants), have been compared. Tests were performed both on small specimens in the laboratory and on full-size structures in the field. It was found that none of the systems waterproofed concrete completely, but that three of them initially reduced the rate of water penetration, particularly under field conditions. Following initial tests, the laboratory specimens were exposed to the weather for four years, after which time the earlier tests were repeated. The effectiveness of the treatments applied in the field was also reassessed after four years. On the laboratory specimens, all treatments had apparently become more effective. In the field, the treatments had evidently retained moisture in the concrete, i.e. they had done precisely the opposite of what is required of a waterproofing system.