The paper presents research of reinforced concrete beams loaded with a torsional moment, a bending moment and a shear force. Cantilever C35/45 concrete beams, made in a real scale with cross section 30x30cm were analyzed. Reinforcement in the beams was formed on the basis of three-dimensional STMs (Strut and Tie Models). The first model was a spatial truss similar to the Leonhardt truss, in which the concrete compression diagonal struts, separated by cracks on each side of the vertical and horizontal element were inclined to the axis of the chords at the angle of 45°. The vertical elements of truss represent reinforcement in the shape of stirrups. The top and bottom chords of the truss represent tension reinforcement and compressed accordingly. In the second STM, the concrete compression diagonal strut were inclined to the axis of the chord at the angle of 37° but in the third STM the diagonal struts were inclined at the angle of 26.6o.Experimental tests of 6 reinforced concrete beams were performed in the laboratory of The Faculty of Civil Engineering and Architecture Environment in Rzeszow University of Technology. The beams were being loaded gradually and for each stage of the load, cracks, the angle of rotation of the cross and displacement were measured. The experimentally determined beam load-bearing capacities TR and stiffness under torsion were compared with the ones calculated from equations based on the well-known theories.