Abstract
Structural design usually does not treat torsional analysis, hence there exist no practical evaluation method of tosional effect. It is attempted to propose a practical method of evaluating torsional effect, making use of ordinary bending moments, shear forces and bending deflections. A set of approximate equations were derived from the stiffeness ratio of the St. Venant's torsion to the Wagner's torsion. Numerical examples were compared with some experimental results, and the proposed method was proved to give practically good prediction of torsional behavior of structural memberes.