Hollowcore slabs are cast using concrete extruders. BPC Group uses PCE extruders which are worldwide used for this purpose. The concrete used in production of these slabs is manufactured under controlled conditions in its own batching and mixer plants employed specifically for captive use only.
The reinforcement strands, as per BS 5896:1980 standards, are prestressed as per the standards with special equipment ensuring all the strands are properly stressed. After the slabs are cast in its casting beds, they are covered with sheets and left as it is to develop the initial strength. The concrete strength is at least 60% of the design strength before tension in the prestressed strands is released from abudments. After the strands are cross cut, strand slippage must remain within the permitted limits.
Quality control is performed according to BPC Group standard quality procedures in the well equipped laboratories. The testing equipment is calibrated and maintained at fixed intervals to ensure the test results are at par.
The material used in production of concrete goes for inspection and testing as per company inspection procedures and British Standards. Compressive strength of concrete is determined by standard test cubes from the fresh concrete and these are tested in accordance with BS 1881: Part 108:1983 and BS1881: Part 116:198
Structural tests are carried out on final product at regular intervals to determine the actual shear and bending capacity of the slabs.
After production, all slabs are visually checked for cracks, broken edges, finish and strand slippage before they are released for delivery.
All Hollowcore slabs are cured as per BS standard and company procedures. During the curing period, the slabs are regularly watered and kept covered with polythene sheets to retain the moisture around them.
A full schedule of company standard quality control procedures can be requested from the Quality Department.
As a special service, we can offer a full Quality Control Report for the individual project consisting of casting dates, cube test and other quality checks for the particular project. This service shall be agreed with our sales department.
BPC Group Quality Control System and standard procedures have been certified to meet the requirements of ISO 9001:2000 standard covering design, manufacture and erection of the company's precast components. The ISO 9001:2000 certificate also ensures that the clients are guaranteed a good product and service throughout the entire project.
Quality Management System of BPC Bahrain, UPC Dubai and UPC Abu Dhabi has been certified by DNV
Erection of the hollowcore slabs is a simple process. BPC Group trained erection crew lead by experienced supervisors ensures that installation fulfil the required specifications.
Erection is carried out in a continuous operation. On steel and precast structures the Hollowcore slabs are placed directly on top of the support. On in situ concrete structures the Hollowcore slabs are placed on plywood shims for levelling purposes.
The erection process will in most cases takes 1 day for approximately 400m2 depending upon the complexity of job.
After the slabs are erected, levelling of slabs will be done within 2 days of erection.
Trained BPC Group crew carries out the erection work thus giving you the maximum expertise and saving of time. Provided certain requirements are observed, contractor’s crew may carry out the erection work.
In this case it is important that lifting and handling of the slabs is done correctly by following the procedure specified by BPC Group.
BPC Group will not take any responsibility for the slabs during lifting, handling and erection if the erection is done by the contractor. We will only guarantee for the slabs after completion of grouting and tamping according to our specifications.
Lifting of slabs:
Slabs are lifted directly from the trailer and into position.
Full slabs are lifted using the specially designed lifting equipment.
When lifting part slabs (width less than 1200mm) and slabs with cutouts near the end, sling belts will be used.
When lifting with clamps safety chains are used underneath the slab. The chain should not be released until the slab is about 100 mm from the support.