EXPERIMENTAL AND FINITE ELEMENT ANALYSIS OF TORSIONAL BEHAVIOR OF INTERNALLY-STRENGTHENED RC BOX BEAMS USING STEEL BRACINGS TECHNIQUE

Abstract

In the present paper, experimental and finite element analysis was performed to investigate the torsional behavior of reinforced self-compacting concrete box beams. The experimental program consists of cast and testing of five simply supported beam specimens under the effect of pure torsion. All beam specimens have dimensions of (2100x300x300mm) for length; width and depth respectively. Each beam was reinforced by (2ϕ12mm) longitudinal bars at the top and bottom, while, the transverse reinforcement consists of (ϕ8@65mm) stirrups at ends and (ϕ8@130mm) stirrups at the mid. The first beam specimen was non-strengthened (reference beam), while, the other beam specimens were strengthened by (three X-Type), (five X-Type), (five XW-Type) and (five K-Type) steel bracing respectively. Tests results show that the ultimate torque moment increased by about (34%), (59%), (72%) and (82%) for beam specimens strengthened by (three X-Type), (five X-Type), (five XW-Type) and (five K-Type) steel bracing respectively, in comparison with the reference beam.