What factors should be considered about All Tech Industries coatings and sealants ability to adhere to concrete?
There is no hard and fast number that is useful to the designer. Generally, an adhesion value is a compromise between the type and condition of concrete substrate, the stresses placed upon the membrane prior to project completion, and the requirements of the membrane to withstand in-place use stresses. Where possible, concrete should have all surface paste removed and be free of latency of any kind. A texture similar to 80-grit sandpaper as a minimum is desirable. Since concrete has low tensile properties, especially at the surface faces of large plan areas, one rule of thumb is to expect adhesion to range around ten percent (10%) of ultimate compressive strength of the concrete. The best that can be expected is in the range of 450 PSI to 650 PSI for 4,000 PSI concrete properly cured and of sufficient age to acquire its maximum physical properties.
