Effects of Transverse Bar Spacing on Bond of Spliced Reinforcing Bars in Fully Grouted Concrete Block Masonry.

Twenty-seven wall-splice specimens reinforced with number (No.) 15 (0.6 in.) deformed bars were tested to evaluate the effect of transverse bar spacing on the tensile resistance of the lap-spliced reinforcement. All specimens were blocks wide and 13 courses tall and were constructed in running bond with all cells fully grouted. In all cases, the lapped bars were located within a single block cell and were either spaced 0, 25, or 50 mm (0, 1, or 2 in.) apart. It was determined that the calculated tensile resistance of the reinforcement was greater for bars that were in contact and furthermore, is insensitive to the magnitude of the transverse spacing provided in the case of noncontact lap splices. It would appear that both the American and Canadian provisions are appropriate for both contact and noncontact lapped bars given the resulting levels of conservatism. [ABSTRACT FROM AUTHOR]