STEPHEN L GARVIN AND IAN H MURRAY Building Research Establishment, Scottish Laboratory

A test programme is described to assess the suitability of the BRE general purpose mortar (GPM) for Aircrete blockwork, in particular to assess the effect on movement and cracking potential. The programme includes tests on mortars, blocks and blockwork panels to assess relevant basic properties, and also large panel tests to assess movement and moisture contents in test walls. The results reported, which do not include the large panel tests, indicate that the compressive, flexural and tensile strengths of GPM are greater than the lightest and weakest Aircrete blocks. However, the results for a designation (iv) mortar and an insulating mortar used for comparison, were similar to the properties of the blocks. The basic properties were found to vary with age, curing and moisture content.