Practical Calculation Method for Crack Torque and Ultimate Torque of Special-Shaped Columns under Actions of Pressure and Torque

The experimental results of crack torque and ultimate torque of six reinforced concrete special-shaped columns under the combined actions of pressure and torque were presented firstly. Then, the calculation formula suggested by the Chinese Code for Design of Concrete Structures for the crack torque and ultimate torque of rectangular columns under the actions of pressure and torque were used for reference to determine the expression forms of crack torque and ultimate torque of special-shaped columns. Moreover, the special-shaped cross section was dealt as a combination of two rectangle cross section. A practical calculation method for crack torque and ultimate torque was proposed by data regression of experimental results.