H.R. ROMAN* and R.H. ROMAGNA***Civil Engineer, PhD – Federal University of Santa Catarina – Department of Civil Engineering – Florianópolis – Brazil **Civil Engineer, MSc – National Service of Industrial Apprenticeship – Company Consultant

The paper describes extensive experimental work on the compressive strength of concrete block masonry. Prisms of three different compressive strength concrete blocks, two mortar grades (1:1:6 and 1:1/2:4,5 – cement: lime: sand) and four mixes of grout were tested in compression. The Young’s modulus of the different prisms was also measured. The prisms were moulded with both face-shell bedded and full-bedded joints. The combined influence of block, mortar and grout strength on the compressive strength of concrete block masonry was determined. The influence of the type of joint on the behaviour of masonry was also investigated. The paper shows the main results and the mode of failure for the different combinations of materials and joints.