J.R. RIDDINGTON, P. JUKES and P.J.B. MORRELL University of Sussex

Many different types of direct tension and flexural tests for determining bond strength have been developed over the years. In this paper the results from finite element analyses of many of these tests are presented. It is concluded that when considering in-plane strength then the direct tension couplet test where the load is applied via bolts that pass through holes drilled in the units is the best test, providing that the units are strong enough and that the average stress at failure is multiplied by an appropriate factor. However when considering out-of-plane strength, then the bond wrench test is most practical, providing that it can be shown that for the particular arrangement being used the stress distribution across the joint is not adversely affected by any clamping being employed or by the bond wrench not being the full length of the unit being tested.