Author
DAVID, M. F. ORR. University College Cork
and
MARTIN P. MANNION, Regional Technical College. Cork

Abstract
It is difficult to obtain contact between block and mortar over the full width of the bed joints in masonry of solid concrete blocks laid flat on face. The use of a template tool to form bed joints of controlled dimensions overcomes this problem. Design codes differ significantly in respect to masonry of blocks laid flat and generally lack information for shell bed construction. Tests on masonry prisms have shown that, for practical widths of mortar strips, the compressive strength of shell bedded masonry is proportional to the area of mortar in the joint. Eccentric load tests on shell bedded prisms indicate that a uniform compressive stress distribution model is adequate for determining the interaction between axial force and bending moment. It is concluded that designers can have confidence that load bearing walls of shell bedded solid concrete block masonry, designed on the basis of rules such as those given in Irish Standard, IS325, have adequate bending resistance to be structurally robust.