Akerman ceilings are made of ceramic hollow bricks with a height 15, 18,20,22 cm, width 30 cm and length 25 cm.
The permissible spans of Akerman ceilings depend on the height of the hollow bricks, the thickness of the concrete topping and the reinforcement used.
• In ceilings with a span of up to 5,0 m, the top layer of concrete topping may not be used, but only level the surface of the ceiling 2 cm with mortar.
• When using thick concrete topping 3 cm The permissible span of the ceiling is 6,0 – 8,1 m – depending on the height of the blocks used.
• A further increase in the allowable span can be obtained by thickening the concrete topping layer to 5 cm and cross slab reinforcement.
The construction of the Akerman floor is slightly different from other ribbed ceilings. Prefabricated truss beams are not used here, but bearing ribs, composed of main bars and stirrups, which are entirely made on site and poured with concrete.
Laying this floor requires rigid and almost full formwork under the load-bearing ribs (a few centimeters apart between the beams). This ceiling is characterized by a relatively low consumption of steel.
The order of execution works is also different from other ceilings: formwork assembly, arrangement of hollow bricks, laying the reinforcement, placement and compaction of concrete, leveling the surface of the slab and curing the concrete.