Concrete flooring is the load-transfer element drawn between steel beams and on secondary beams.
Click the Steel Slab icon from the ribbon menu .
The steel laying toolbar will open.
Click on the settings icon on the far right. It contains the opened concrete thickness, material and load information parameters.
Choose the first of the steel beams.
You have selected the steel beams to form a closed polygon and finish by right clicking on the last beam.
Your concrete floor will be formed.