8 Pages

Tension Field Action in Composite Plate Girder Webs

WithN. E. Shanmugam

The paper is concerned with tension field action in steel-concrete composite plate girders subjected to combined shear and positive or negative bending. Composite plate girders have been tested to failure in order to study the tension field action and ultimate load behaviour. Two different web depth to thickness (d/t) ratios viz. 150 and 250 were considered. Attention is focused on the variation in tension field action in web panels due to composite action between steel girder and concrete slab. Extensive strain measurements have been made on the web panels in order to obtain a detailed picture of tension field action. Brief account of the experimental investigations on steel concrete composite plate girders is presented in the paper. Results obtained show that the width of yielded tension band increases due to composite action of slab with the steel girder and the action is more significant in the case of plate girders with slender webs. Increase in load carrying capacity is also observed for composite girders with thicker webs, but of smaller magnitude compared to the girder with slender webs. Results are also compared with those obtained from nonlinear finite element analyses.