Shear behavior of partially encased composite I-girder with corrugated steel web: Experimental study

A new type of partially encased composite I-girder with corrugated steel web has been proposed to improve the structural performance of continuous girders under hogging moment. The shear behavior of such partially encased composite I-girders under anti-symmetric loading has been experimentally and analytically investigated. Experimental results show that the partially encased composite girders has superior shear strength compared to steel I-girders, since shear bucking of steel web is restricted by concrete encasement. The shear stiffness of the composite section is based on the total summation of corrugated web and concrete encasement with average thickness before cracking, and the ratio of shear resistance shared by the steel web and the concrete encasement depends on their shear stiffness. In addition, predicted shear strength of the partially encased composite girder with corrugated web is proposed according to the experimental failure mode and strain distribution. The analytical shear stiffness and shear resistance ratio at the elastic stage are verified by experimental results. And the calculated shear strength for steel and composite girders agree well with the experimental results. The comparison shows that the proposed analytical methods can be applied in predicting elastic shear stiffness and design shear strength for such partially encased composite girders with corrugated web.