A. W. HENDRY University of Edinburgh

One of the basic problems in the design of masonry structures is the calculation of the strength of walls under compressive load. This paper discusses the various aspects of this problem with particular reference to the Code of Practice BS 5628: Part 1 and the Draft Eurocode ECS.
Assuming that appropriate materials’ properties are known a mathematical representation of the element behaviour is adopted which will take into account the effects of slenderness and eccentricity. This in turn requires the determination of eccentricity of loading and some means of allowing for departures from idealised conditions inherent in the theoretical solution.
The methods used in BS 5628 and in EC6 for the derivation of capacity reduction factors, the determination of eccentricity and slenderness ratio are reviewed in the light of available evidence. It is found that the reduction factors by the EC6 formula are about 10% lower than by BS 5628 if comparison is made on the basis of equal eccentricity of applied load. The introduction of additional eccentricities relating to imperfections of construction and creep in EC6, however, leads to a much more conservative result. The method of allowing for these effects thus requires examination and further research.