The Connectors' Deformation And Mechanical Performance Of Cold-formed Thin-Walled Steel And Concrete Composite Beam

Cold-formed thin-walled steel and concrete composite beam, a new type of composite beam, shows excellent mechanical property and has great economical value. And so researches on it's flexural capacity benefit the engineering practice and economics. The main aspects studied in the paper are above:Cold-formed thin-walled steel and concrete composite beam's finite element modal is set up and both material and geometric nonlinearities are taken into account by using program ANSYS,and also connectors' slip at interface are concerned.Connectors' slip on composite beam is studied,and influence by loading form, connectors' interval, loading grade and end-plate's demension are analyzed. Simplified slip calculating modal is set up and formula is presented after slip under uniform loading, concentrated loading at mid-span and concentrated loading at tri-span is studied.Deflection influenced by connectors' slip is analyzed with the modal of cold-formed thin-walled steel and concrete composite beam, results calculated by standard formula are compared with the results calculated by simplified modal formula and curve type of the standard formula is studied, and then the applicable scope of the standard formula is put forward.Flexural capacity influenced by connectors' slip of the cold-formed thin-walled steel and concrete composite beam is analyzed. Simplified formula for calculting elastic flexural capacity is given when slip is cencerned; Simplified plastic theory is modified and formula for modified coefficient is given when calculating ultimate flexural capacity; Another method for calculating ultimate flexural capacity is presented which base on plane section assumption,and the reduced coefficient caused by slip is given.