FEATURES & ADVANTAGES
Teemage Hollowcore Slabs are pre-cast in the controlled environment of the factory away from the building site.
The designers have greater flexibility because of the varying thickness (150 - 400 mm) available and larger spans up to 18 meters can be obtained at costs which are lower than conventional flooring systems.
Quality of Hollowcore slabs are much higher than conventional methods just because of the state-of-art machines being used and continuous quality measure taken during the production process.
The casting is sequenced in such a way that every floor of your building are stored and ready to be delivered for installation as quickly as required at the site.
Expensive formwork and propping is eliminated thus improving productivity and access within the site is vastly improved.
A Hollowcore slab, also known as a void Slab or hollowcore plank, is a precast slab of prestressed concrete typically used in the construction of floors in multi-story buildings. They are widely used throughout the world as flooring and roofing solutions.
HollowCore slabs are produced worldwide using a variety of manufacturing processes. Teemage Precast In has chosen to use a Slipformer production system developed by Echo Precast Engineering. This state-of-the-art system is a dry cast, extrusion process where zero slump concrete is forced through the machine. The cores are formed with augers and tubes with the concrete being compacted around the cores using high frequency vibrators.
Teemage Hollowcore slabs are nominally 1200mm wide and are available in thicknesses of 150mm, 200mm, 250mm, 300mm and 400mm. All the slabs are cast with high strength prestressing cables to provide the load carrying capacity. Depending on the requirement of the client, our team of specialised designers will provide the most efficient product.
Hollowcore slabs are widely known to be used in all forays of construction including but not limited to the following.
Shopping malls, Retail showrooms, corporate office buildings
Schools, Colleges, Hostel buildings, Auditoriums
Hospitals, Nursing homes, elderly care facilities
Boundary walls, tank cover slabs, ramps
Multi-storey apartments, High-end Villas, Mass housing projects
Manufacturing facilities, power generation plants, heavy industries
Multi-level car parks, underground parking facilities
The availability of design softwares and load charts derived from the same provides greater flexibility and ease in the application of hollowcore flooring. Teemage Engineers have prepared load charts (provided upon request) that gives the designer the opportunity to quickly size a hollowcore floor slab for a particular load case. The floor span length is the primary consideration during the design process. For a framed structure the most economical grid is to maximise the span of the hollowcore slab and minimise the span of the support beams with a minimum number of load paths. Hollowcore floor slabs are best suited as simply supported one way spanning slabs, where lateral restraint of the building is provided by shear walls. Alternatively, connections between vertical elements and hollowcore flooring can be designed to resist moments generated due to Wind or Earthquake loads. Also, multi-span hollowcore flooring structures can be designed to promote continuity.
ManufactureThe advantage of controlled concrete production in enclosed factories is obvious, Every part of the process can easily be monitored and controlled, because the operations are repetitive and take place at the same location. Hence it is economically justifiable to carry out the necessary investments to meet the demands of our modern, ecologically conscious society.
Floor depthThe load span charts can be used for a preliminary selection of a floor slab. Two options, with and without a nominal concrete topping of 50mm has been used for all slabs and can be chosen based on the load considered.
Slab widthIt is preferable that the floor plan dimensions suit a 1200 mm modular width. Non modular dimensions can be accommodated with longitudinally cut slabs or wet-cast slabs.
Slab lengthThe slabs are cut to the length required for their location in the floor plan. The ends can be cut to an angle to suit skewed layouts.
LoadsThe Hollowcore slabs are typically designed to take superimposed uniformly distributed dead and live loads generated based on their occupancy. Concentrated permanent loads and construction loads higher than normal can also be catered to based on their magnitude.
ConnectionsTeemage Precast uses European and American Standards for connection details between hollowcore floor slabs and the supporting beams or walls. The connection details at a support must not only transfer load but also contribute to the monolithic behaviour of the entire structure. Although, most suitable for a Total Precast system, hollowcore slabs can also be provided for and connected to Cast-in-situ structural framing, steel frames, masonry walls etc. Detailed connections shall be provided during the preliminary meeting with the client based on their exact requirements.
Camber and ScreedingHollowcore floor slabs are cambered because of the upward bending induced by the prestressing tendons. This camber should be allowed for in detailing the slabs. A cast-in-situ screeding unifies the individual slabs into a monolithic floor, takes out differential levels between slabs and provides a uniform working surface.
Fire resistance levelThe FRL is normally varied by changing the cover to the strands and generally adding topping to the floor. This is effective up to a fire resistance period of 180 minutes. Flexural continuity at one end of a span for imposed loads substantially increases the fire resistance period for structural adequacy or enables a reduction in cover. A typical hollowcore slab system is designed for a 2hr fire rating without need for extensive detailing or costs.
This specification is intended to be used as a guide to preparing the general project specification or as a stand alone specification.
- Thickness - 150 mm
- Span - 3- 6 mtr
- Thickness 200 mm
- Span 9 mtr
- Thickness 250 mm
- Span 12 mtr
- Thickness 300 mm
- Span 13.5 mtr
- Thickness 400 mm
- Span 16 mtr