BPC Group offers a wide variety of precast panels, which we are divided into the following 3 categories:
Precast panels are used in high-rise buildings, villas, commercial and office buildings as well as industrial buildings, where emphasis is on prestige and aesthetic appeal, or where economy and durability are of importance.
To ensure the most optimal solution of each individual project the company’s early involvement in the design phase will ensure considerable time and cost saving for the project.
Cladding panels are defined as non-load bearing architectural panels, which only fulfil an enclosing and decorative function in the façade. The combination of finish and shape contributes to the architectural expression and finished appearance of the structure.
The panels are normally single skin units, but can be made as a sandwich panel if required.
Standard thickness of single skin units are 100, 120, 150 and 180mm.
These panels are designed as individual panels, which only supports itself and does not contribute to the overall building structure at all. Only load on panels are self-weight and wind-load for which 45 m/s wind-speed is allowed for, as per British Codes.
Design-wise the following 3 parts shall be done when designing a structure with Precast cladding:
1. Design of the Precast cladding part.
2. The support of the Precast panels, which provides vertical and horizontal support for the panels.
3. The connection that joins the Precast units to its support.
Precast cladding can be fixed to steel frame structures as well as concrete frame structures.
In general, the panel should be supported vertically on a corbel in only one location and mechanical fixing will take the horizontal load, allowing the panel to expand / contract due to thermal movement.
For fixing to steel building frames, the overall static system can be the same as for concrete structures. However, the details are different, since fixing arrangements are normally pre-welded to the steel structure.
Another static system is that the cladding panels are self supported directly on the foundation and only horizontally fixed to the main structure.
- Where future expansion of the main building is in mind during the design stage, then without disrupting the flow of the rest of the facility, the Precast panels allow for space to be added easily using the same design.
- Eliminates the risk of hand-setting stone or brickwork in potentially hazardous locations.
- Custom-made steel moulds are used to create panels in the exact size and shapes specified by the designer, as well as to introduce reveals, joints, patterns and other architectural detailing to the panel surface.
- Specific colour effects can be achieved by varying aggregates, cements, pigments and different surface treatments.
INSULATED SANDWICH PANELS
In addition to aesthetics, Precast panels can be manufactured with built-in insulation material, reducing the thermal U-value dramatically, and thereby improve the cost of running the building as reduced A/C-capacity is obtained. This also creates a balanced comfortable and healthy in-door climate.
Insulated sandwich panels can be used both as cladding panels and load bearing panels with or without architectural shapes and finishes. The optimal and economical use of architectural Precast concrete panels is achieved, when the panels serve as load bearing, supporting vertical loads from other members and at the same time as shear walls to cope with horizontal forces.
Sandwich panels are widely used in villas, offices, hotels and industrials buildings where effective thermal and noise control is required. The panels are designed for horizontal wind pressure as well as vertical dead and live loads.
Standard thickness of sandwich panels are 200, 250, 270 and 300mm. However most thicknesses required by the client can be achieved.
All designs are according to British standards with regard to wind load and concrete strength.
BPC Group has developed 2 standard types of insulated panels:
IP (Type – I)
This is the optimal way of making insulated sandwich panels with regard to thermal resistance. The Type-I panel consists of two concrete layers with an insulation layer in between, fully separating the two concrete layers. The external layer can be made in gray concrete for painting or in colored architectural concrete with several options on surface finishes. The internal layer is normally always gray, with a smooth finish ready to receive paint.
Standard thicknesses of Type-I insulated sandwich panel is 250, 270, 300 and 350mm.
The external layer can vary from 50mm to 70 mm depending on the thermal requirement as well as the insulation material.
The internal layer of concrete varies from 120mm upto 220mm in thickness depending on the structural requirements.
For big panels, or high loads, the internal layer is normally built up as a frame system (columns and beams), where columns and beams will cope with the load, and in between the thickness will be reduced to min. 70mm.
Depending on insulation material and thickness, the Type-I panel U-value ranges from U = 0.8 W/m2K to 0.25 W/m2K.
The external layer (outer skin) is designed to hang from the internal load bearing part by means of stainless steel hanger bars and connectors.
By doing so, the external skin is allowed to expand or contract independent of the internal wall due to the temperature difference between interior and exterior of the building.
The internal part will more or less always have the same temperature, as indoor temperature in a building normally is maintained at the same level throughout the year, meaning that the risk for thermal cracks is reduced to a minimum. For the external skin the panel joints are sealed by mastic sealant, which allows movement due to change in surface temperature.
IP (Type – II)
Our Type-II sandwich panels are considered as a good alternative to the solid panel or traditional block work, for which the thermal resistance is improved to being twice as good. The U-value of this panel is approximately U=1.0 W/m2K up to U = 1.8 W/m2K depending on the insulation material used.
The Type-II panels can be manufactured with all the other advantages, which are mentioned under Type-I, load bearing as well as non-load bearing panels.
Standard thickness is 200mm, with 75mm internal and external skin and 50mm insulation in-between. However compared to Type-I the internal and external skin are not completely separated.
All the four sides of each panel are solid reinforced concrete, where the two vertical sides act as columns, with the top horizontal side as a beam and the bottom horizontal side as a stiffener.
When sandwich panels are used as load bearing panels in complete Precast buildings, proper tying system is required for the transfer of lateral forces by diaphragm action of Hollowcore slabs.
The connection between the panels, is by shear key arrangement.
The outer skin can be extended to form a parapet, thus eliminating the need to build an in-situ parapet with block-work or concrete.
The amount saved in energy consumption is substantial in the long run, and the required A/C system can be reduced in size, giving initial savings, comfortable and healthy indoor climate.
- For industries which have to meet thermal and noise pollution control, the insulated sandwich panels are the ideal solution as they come with the required system in-built, saving time and money on any after construction measures to be taken to meet the required criteria.
- The internal surface comes ready to receive paint.
- The external face can have any architectural effects and colours to suit the need.
OTHER ARCHITECTURAL PANELS
As BPC Group is continuously trying to develop new methods and improve old ones, we also produce more special architectural panels.
In these cases there are no standard types, each project and even each panel is individual and unique. These are the kind of projects where boundaries are pushed, new limits are achieved and where architecture and engineering meet and collaborate to reach new standards.
Furthermore architectural concrete is perfectly suited for complicated geometric shapes and forms, which would otherwise prove to be prohibitively expensive in traditional methods of construction.
Solid panels can be used as interior and exterior panels. For exterior panels the advantages mentioned under cladding panels can be achieved, however for load bearing panels basic structural requirements are to be fulfilled for transferring horizontal and vertical forces.
As a standard, BPC Group produces 120, 150, 180 and 200mm thick load bearing wall panels and 100mm thick non-load bearing wall panels; however any thickness can be produced if required.
Where solid panels are used as building systems, the height and length of the panels will be as required for room height and length, so that the grouted connection between the panels appear only at room junctions.
In plan the panels are connected by shear key arrangement as shown below on D-13.
Vertically the panels are connected by a T16 dowel-bar, projecting from the lower panel onto which the slot provided in the upper panel will fix into. Horizontal connections between panels are normally grouted shear keys.
Proper tying system as required for the transfer of lateral forces by diaphragm action of Hollowcore slabs has to be taken care of in the connection.
- They can be designed to act as shear walls thus eliminating the need to resize the columns and beams for lateral forces.
- 150mm thick Precast panels provide more floor space compared to load bearing block walls and columns and beam frames that normally cannot be done lesser than 200mm.
- Erection is very fast and time saving.
- Electrical conduits and boxes are cast into the panels
- Precast panels are manufactured with smooth internal surfaces ready for painting.
- High durability, which is important on external surfaces. No cracks or similar surface defects will provide very low maintenance and long lasting exclusive appearance.