and D.W. HOBBS
British Cement Association

Bond strength results obtained using the crossed couplet and wallette test methods are reported on 1:6 air entrained cement.sand mortars prepared using two cements. The results are compared with the results obtained by other investigators. It is shown that the wallette bond strength is higher than the crossed couplet bond strength. Due in part to the lower coefficient of variability which can be obtained using the crossed couplet method, it is concluded from these results that this method is preferable to the wallette test as a method of determining bond strength.