The effectiveness of mortar layers used to prevent degradation of adhesives and floor coverings on concrete slabs was investigated. Concrete samples 400 x 600 mm were used in conjunction with four floor coverings ( vinyl and linoleum carpet, oak and beech parquet ) and three adhesives. Measurements included temperature, pH and relative humidity in the concrete, and the floor covering bond strength. It is suggested that a thin fine smoothing mortar layer be installed soon after casting, and allowed to dry uncovered for several days-several weeks. A low alkali layer minimises adhesive and floor covering degradation in high moisture environments, and alkalinity and high hydroxyl ion concentrations in the concrete pore water. These benefits are lost if the mortar layer cracks, allowing moisture and reactive ions to reach the adhesives and floor coverings. 10 refs.
Primary author(s): Rasanen V;Eronen J;Wirtanen L;Penttala V
Vol.56, No.1, 2004, p.45-54