Test on pure torsion behavior of channel steel reinforced concrete beams

This paper totally reports the results of 8 pure torsion tests on channel steel reinforced concrete beams (CSRCB) and one pure torsion test on normal reinforced concrete contrast beam. The variables studied were the concrete strength, the configuration form of stirrup, and the form, angle, spacing of lace bar. It is shown that the concrete strength, stirrup disposition and channel steel have significant effects on the torsional capacity of the beam after comparative analysis. The failure mode and crack patterns of test specimen are investigated, also the working mechanism of channel steel and the concrete are analyzed in this paper. Finally, a calculation formula for cracking torque and ultimate torque of CSRCB are proposed. Good agreement was demonstrated between the test results and the calculation results which indicates that the calculation formulas proposed in this paper are applicable to the calculation of cracking torque and ultimate torque of CSRCB.