Nonlinear nite element analysis of RC beams under combined shear and torsion to extract linear and curvilinear ranges of interaction curves

The use of non-linear nite elements to assess the eect of transversereinforcement amount on the shape of shear-torsion interaction curve for rc beams isaddressed. at rst, fem results for specimens under pure torsion and combined shear andtorsion were validated with previous outcomes. secondly, reference specimens were madewith the minimum required transverse reinforcement at rst. each specimen was analyzedwith the nite element method and tested under similar conditions in the laboratory, andthe results, including the cracking pattern, cracking and ultimate loads, and shear-torsioninteraction curves, were found to be in very good agreement. finally, the transversereinforcement amount was increased to certain extents and similar results were determined.fem interaction curve stood below the experimental curve. it was also deduced that,from a certain increase in the transverse reinforcement, the shear-torsion interaction curvetransforms from linear to elliptical.