Voided Slab System

According to Wikipedia: Voided slab system, sometimes called biaxial slabs, are a type of reinforced concrete slab that incorporates air-filled voids to reduce the volume of concrete required. These voids enable cheaper construction and have a less environmental impact. Another major benefit of the system is its reduction in slab weight compared with regular solid decks. Up to 50% of the slab volume may be removed in voids, resulting in less load on structural members. This also allows increased weight and/or span, since the self-weight of the slab contributes less to the overall load.

Volimax voided slab system reduces the weight and thickness of the slab, increasing the earthquake resistance of the structure without compromising the performance attributes of a flat slab. Beamless voided slab distributes the design loads to the four sides, transferring them to the columns/walls or beams. Volimax voided slab disposable formworks create a matrix of 𝙸 shaped beams working in both directions of the plane. What is voided slab system?

Volimax – Voided Slab System

Architectural Advantages

  • Wider axial openings
  • Reduction in slab cross-section
  • Gains from floor height
  • Reduction in shear wall dimensions
  • Reduction in the number of columns
  • Flat and continuous ceiling
  • Sound insulation

Structural Advantages

  • Working in two directions
  • Reduction in building self-load
  • Reduction in displacements
  • Reduction in loads on the foundation
  • Reduction in earthquake impact

Cost Advantages

  • Casting in situ
  • Shorter construction time
  • Less concrete consumption
  • Less steel consumption
  • Easy to use
  • Ease of material logistics; less storage space, more efficient transport

Voided Slab System – The Most Efficient Slab System

A growing number of innovations has revolutionized the construction industry with the aim to make the buildings sustainable and efficient. Innovations in designs, materials, management and execution all contribute to the improvement of the construction.

One of these design innovations is the Voided Slab Design. The voided slab is a system that gets rid of the non-functional and non-load-bearing concrete slab parts by incorporating air-filled voids. This results in a massive reduction of concrete volume which will give benefits such as savings, speed, safety and sustainability (4 S Benefits).

Voided Slab and Solid Slab Comparison

Savings. Significant reduction of concrete volume (35%) means lightweight buildings, fewer design loads, longer span (maximum of 20m span), 40% reduction of required columns, time and labour cost savings, reduce forming works, and optimize vertical and horizontal space.

Speed. Lightweight building design results in the elimination or at least reduction of required beams and columns which will require less time for forming, pouring and curing concrete, and no outrigger (lateral bracing) required. Compared to the PT slab, there is no specialized subcontractor required as the main contractor can execute the voided slab.

Safety. Lightweight construction has a huge advantage in seismic design. Voided slab system has 20% fewer earthquake loads, fewer internal inertia forces, accelerated mass reduction and lower damage risks. Voided slab system is the most fire (4-hr rating) and sound resistant of all types of slabs.

Sustainable. Due to the reduction of concrete volume, the building with voided slabs prevents 20% toxic emissions. This also means savings on the energy required to make and transport materials and savings on natural resources i.e., water, concrete and steel bars. CME void formers use recycled plastic.