EXPERIMENTAL AND NUMERICAL INVESTIGATION ON TORSION STRENGTH OF STEEL HOLLOW SQUARE SECTIONS STRENGTHENED WITH CFRP WRAPS

Abstract

This research aims at studying the effect of strengthening steel square hollow sections subjected to torsion with CFRP wraps, Test set-up was designed and implemented to transfer the tension force in the lab to pure torsion on the test specimen. Experimental investigation was conducted on Eight SHS specimens including control bare specimens and strengthened specimens with different strengthening configurations. Recorded results proved the efficiency of strengthening SHS’s with CFRP wraps. Finite element models were constructed to simulate the tested specimens and a failure criterion was concluded based on total strain energy in the numerical model and was verified with the test results and work from literature. Parametric study was conducted to assess the influence of the independent variables on torsion strength, stiffness gained by strengthened specimens. Design equations to calculate the torsion strength gained by the adopted strengthening techniques were established by regression analysis using the numerical results and were verified with the experimental, numerical work conducted herein and with work from literature.