Investigations on Beams with Multiple Regular Web Openings

In recent years the application of cellular beams is more and more requested by architects and designers. Not only their aesthetical appearance as visible steel structures and economic design are popular, also the possibility to pass service integrations through the openings is given. In the scope of the ECSC project 7210-PR-315 "Large web openings for service integration in composite floors" the performance of beams with web openings was studied experimentally and theoretically. The aim of this paper is to present the investigation on beams with multiple regular web openings with special focus on different failure mechanisms. The test program comprehended large scale tests with the following objectives: (1) Composite action close to support, (2) Behavior of elongated openings, (3) Load introduction via secondary beams, (4) Asymmetric design, and (5) Stiffening of web openings. On the basis of the test results and theoretical investigations including numerical simulations, design recommendations were established.