partial to full composite action in steel–concrete sandwich beams: development of a modeling strategy and comparison to standards

In modular steel–concrete–steel (scs) structures, a partial composite action may appear in some unfavorable conditions, requiring the modeling tools to be adapted to both full and partial composite actions. this study thus proposes a refined simulation methodology, including regularization techniques in tension and compression, to assess full and partial composite actions in scs structures using 3d finite elements. it is validated on two three-point bending beams. a good agreement on global (resistance) and local (failure mode) experimental quantities is obtained. the modeling strategy is then used to discuss the transition point between the full and the partial composite actions in terms of stud spacing. this numerical analysis is finally compared to existing standards requirements, which shows a good agreement between standards and confirms their conservative tendencies in most situations