Experimental research on shear bearing capacity of encased steel box-concrete composite beam with short span ratio

Shear experiment on 5 encased steel box-concrete composite beams with short span ratio is presented including specimen design, test scheme, failure characteristics and test results. Influence of span ratio, ratio of stirrup, ratio of reinforcement, concrete thickness above and below steel box and shear studs on shear bearing capacity of this beam is researched, and important components of shear bearing capacity of the beam are analyzed. On the principle of contribution of the surrounding concrete to shear bearing capacity being the same with that of ordinary concrete, applying bottom envelope curve method, contribution of encased steel box to shear bearing capacity is derived, moreover, calculation formula of shear bearing capacity of this kind of beam is obtained.