Biaxial shear behavior of steel reinforced concrete column

The objective of this study was to clarify shear behavior of the steel reinforced concrete columns with biaxial shear experimentally and theoretically. Six specimens were tested. All specimens have cross section of 250 mm width x 250 mm depth and the column height of 500 mm. Cross-shaped steel was encased in the column. Experimental variables were the loading angle to the principal axis of the column section and the ratio n =N/N-0 of the applied axial load N to the compressive strength of the column No. The loading angle was 0 and 45 degree to the principal axis. The applied axial load was 0, 0.2N(0) and 0.4N(0). From the test results, maximum strengths of the steel reinforced concrete columns with the loading angle of 45 degree were larger than those of the steel reinforced concrete columns with the loading angle of 0 degree, and hysteresis loops showed large energy dissipating capacity up to the story drift angle of 0.05 rad. regardless of the applied axial load. The resistance mechanism of the steel reinforced concrete column with biaxial shear was proposed. Based on this mechanism, a method capable of predicting the ulimate shear strength with biaxial shear was proposed.