These procedures are useful for research into bond strength of masonry. They are not intended to predict the bond strength of commercial masonry construction. The bond strength in commercially built structures is determined by many factors beyond the characteristics of mortar, masonry units, and the procedures of this test method.

Note 1-The crossed-brick couplets method measures a direct tensile strength of the bond between the mortar and masonry unit. It does not determine the flexural strength of the unit mortar assembly. Other test methods may be more appropriate for determining the flexural bond strength between mortar and masonry units. These include, C 1072 Test Method for Measurement of Masonry Flexural Bond Strength, C 1357 Test Methods for Evaluating Masonry Bond Strength, and E 518 Test Methods for Flexural Bond Strength of Masonry.