Parameters Affecting the Shear-Friction Strength of a Construction Joint in a Squat Wall Subjected to Cyclic Loading

In the present study, the seismic shear-friction behavior of squat reinforced concrete walls with a construction joint was investigated. To investigate the effect of flexural moment on the shear-friction behavior, 10 wall specimens—rather than conventional push-off (direct shear) specimens—were tested under cyclic lateral loading. The test parameters were the surface roughness, surface roughening method, reinforcement ratio, reinforcement diameter, section geometry, wall aspect ratio, and reinforcement arrangement. The test results showed that roughened interface increased the shear-friction strength, but the difference between roughening methods was marginal. When large diameter rebars were used, the strength degradation due to the cyclic loading effect was less significant. Further, even when the overall amount of reinforcement was uniform, the shear-friction strength increased as the flexural strength–demand ratio increased due to the low aspect ratio and the use of flange. The test results, along with previous studies on shear-friction walls, were compared with the predictions of current design codes, and the effect of design parameters affecting the shear-friction strength were discussed. A nonlinear macro shear-sliding model for shear walls overestimated postyield strength and initial stiffness and underestimated residual strength.