What is a hollow core slab? - Elematic precast technology
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Hollow core slab

Hollow core slabs are pre-stressed floor products with either round or shaped voids, depending on local requirements. The hollow core slabs can be either extruded or slipformed .

A hollow core slab – the most used precast floor slab

The hollow core slabs are manufactured on long-line beds that are typically 120 – 150 meters long. The units may be manufactured with a thermal insulation layer on the under-side—for example, for floors at ground level. The slabs are cut to length using a circular saw.

The nominal width of the units is 1200 mm. The various cross-sections are given alongside. Their thickness is 120-500 mm and casting width 1.2–2.4 m. Excellent load-bearing capacities and longer spans give freedom to architectural and structural design.

Application:  Floors for both commercial buildings and homes. It can also be used as a roof or a wall element, for example, in storage buildings or as a fence element.
Due to pre-stressing, the hollow core slab can span up to 23 m, easily in the range of 5.0 to 10.0 m for typical residential buildings. The number of vertical structural components, like column-beam or structural walls, can be reduced substantially using the pre-stressed hollow-core slabs.

Advantages of hollow core slab:

  • Lightweight – reduced concrete and rebar
  • Excellent load-bearing capacity
  • High spanning capability
  • Fire resistance of 60 to 120 minutes but can be extended to 240 minutes
  • Easy to transport, handle and erect

The efficiency of the hollow core slab production

  • It is the most efficient precast element production system
  • The system can be highly automatized, resulting in
    • Compact precast plant layouts
    • Relatively low labor requirement
    • High efficiency of production

Production lines

Strand calculation tool