Evaluation of contact and noncontact lap splices in concrete block masonry construction

Contact and noncontact lap splices, where the lapped bars were located in adjacent cells, were tested in both double pullout and wall splice concrete block specimens. Eight replicate specimens of each type were tested to evaluate whether differences in the reported quantitative results were statistically significant. Visual observations of the incurred damage were also reviewed to identify the resulting failure modes. A statistically significant difference was found between the results of the double pullout and wall splice specimens with the same reinforcing arrangements, and for the different reinforcing arrangements in the same specimen type. Specimens with contact lap splices failed due to bar pullout. Evidence of bond loss at the grout-block interface was observed for specimens with noncontact lap splices and appeared to have influenced the resulting failure mode and lap splice resistance.