Title:
Shear-Friction Strength of Squat Walls with Flanges under Cyclic Lateral Loading
Author(s):
Jae-Han Oh, Ju-Hyung Kim, and Hong-Gun Park
Publication:
Structural Journal
Volume:
123
Issue:
1
Appears on pages(s):
155-170
Keywords:
cyclic loading; flanged wall; shear-friction strength; shear wall
DOI:
10.14359/51748930
Date:
1/1/2026
Abstract:
Nuclear power plants use reinforced concrete shear walls with flanges for lateral load-resisting systems. The present study investigated the shear-friction strength of reinforced concrete walls with flanges by testing eight wall specimens under cyclic lateral loading. The test parameters were the flange length, flange configuration, wall thickness, interface roughness, and load direction. The test results showed that vertical reinforcing bars in the flanges, as well as the web, increased the shear-friction strength of the walls. However, due to the premature punching failure at the web-flange joint, the contribution of the thin flange was limited. Further, the shear-friction strength of the symmetric flanged wall was identical, regardless of the load direction: the shear-friction strength of the flanged wall was determined by the total vertical reinforcing bars placed in the web and flange. The tested shear-friction strengths, including previous test results, were compared with the predictions of current design methods. Including the flange contribution in the current design methods improved the prediction of test results compared to the case neglecting the flange contribution.
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