Abstract:
To study the shear capacity of reinforced concrete (RC) beams without stirrups, nice RC beams with high ductile concrete (HDC) jacket, one RC beam with high-performance composite mortar jacket and three RC beams with no extra reinforcement were tested. The failure mode, shear capacity and deformability of all beams were studied for different shear span ratios and thickness of HDC jacket, and with or without stirrups in the HDC jacket. The test results showed that the HDC jacket can significantly improve the shear capacity and deformability of the beams, and can partially substitute stirrups by improving the shear failure form and increasing the threshold of the shear pressure ratio of the test beams. The thicker the HDC jacket, the more significant the improvement in the shear capacity and deformability. However, measures should be taken to prevent peeling damage when the HDC jacket is becoming too thick. Configuring stirrups in the HDC jacket can further improve the shear capacity and damage resistance ability of the strengthened beams. A formula was proposed to calculate the shear capacity of the beams, and the calculated values agree well with the test values.