The Torsional Performance Research On T-shaped Composite Beams With Corrugated Steel Webs

T-shaped composite beams with corrugated steel webs is a neotype steel-concrete composite structure which use the thinner corrugated webs instead of traditional flat steel webs or concrete webs.It possesses many advantages,such as saving steel quantities,lighter weight and better economy.This composite structure has been widely applied in crane girder,bridge engineering and high-rise building in recent years.With the advent of the long-span bridges and the large-span spatial structures,the torsion problem caused by eccentric loading is gradually come into notice.But in previous studies about torsion problem,it has not been involved in the field of T-shaped composite beams with corrugated steel webs.To fill in the blanks and acquire torsional behavior,the paper will make systematic study on pure torsional performance of Tshaped composite beams with corrugated steel webs in the ways of experimental investigation,finite element method and theoretical analysis.The paper mainly completed the following work:(1)An experimental device was designed for pure torsional test and the test of pure torsional behavior of T-shaped composite beams with corrugated steel webs was accomplished.The failure mechanism of T-shaped composite beams with corrugated steel webs and the crack formation and its development rule on the concrete slab was revealed by experimental investigation.The paper analyzed the relationship between torque and twist rate and strains from the test result,and the corresponding changing curves were drawn at the same time.The deformation characters and the torsional stiffness changes of concrete slab and corrugated web were acquired from the test process and result under pure torsion effect.(2)In this paper,a finite element model was set up by analysis software ANSYS for simulating T-shaped composite beams with corrugated steel webs under pure torsion effect.The results from the test and the FEM analysis were in good agreement,which indicated that the finite element model established was relative accuracy on the pure torsion of T-shaped composite beams with corrugated steel webs.By conducting parametric analysis,it proved that the thickness and height of web had some influence on the ultimate torque of T-shaped composite beams with corrugated steel webs.(3)According to the geometric property of corrugated web,the paper put forward a new calculation method to the torsion stiffness of corrugated web.The paper also summarized the calculated methods about cracking torque and ultimate torque of composite beams,and compared with test value.By contrasting,the paper analyzed the applicability of existing formulas about cracking torque and ultimate torque of Tshaped composite beams with corrugated steel webs.In the last,the existing formulas of ultimate torque was modified and a formula which considered the torsional action item of H-beam with corrugated webs was put forward.