Abstract: The present invention relates to improvements in the construction of roofs, floors, and more specifically, to a structure permitting the pouring of reinforced concrete without the need of other frames or centering. This becomes possible by using a beam with hollows (structure type) having the capacity for supporting without deflecting the weight of elements which make up the slab thereby enabling the beam to be self-supporting. A counter brace helps support the filler elements and the reinforced concrete.