Following the successful launch of its total precast system for multi-storey buildings in Bahrain last year and the completion of its first precast 11-storey building within a record time of five months, Bahrain Precast Concrete Company (BPC), is riding the crest of a success wave that has brought it a string of projects in its wake.

The successful completion of its first multi-storey building has infused confidence in the construction industry regarding its expertise in this field and has already earned orders for 13, 18 and 24-storey precast building systems – the latter being the tallest precast building in the Middle East, says a spokesman for the company
What’s more, it has also received enquiries for further precast buildings including a 50-storey building, he adds.
The spokesman elaborates: “After completing the first 11-storey precast structure in March this year, BPC started work on a 13-storey precast building system for a hotel complex. The scope of work includes 2,220 sq m of 300, 250 and 200-mm-thick shear walls, 5,900 sq m of 300, 250 and 200-mm-thick external insulated load-bearing panels, 840 m of columns (300 by 400), 4,000 m of beams, 10,000 sq m of 150 and 200-mm-thick hollowcore slabs and staircases.
“The load-bearing panels – which are heavy and employ complicated reinforcement - are in two different colours and feature two different aggregates but with the same finishing (sandblasting). BPC is doing this for the first time.
“In addition, since the building comprises a totally precast building system, BPC is also the main contractor for the project. As none of our mobile cranes could be utilised for the erection of the elements on this high-rise building, the company has procured a tower crane for the erection. This crane is under assembly and will be utilised from the third floor onwards.
“Work is in full swing and erection of elements upto the second floor level has already been completed. BPC expects to hand over the building by the year-end.”
Among the most striking contracts that BPC has secured is the one for a 24-storey twin office tower, which “will by far be the tallest precast building superstructure in the Middle East and possibly in the world,” according to the spokesman. “There are taller precast concrete buildings elsewhere in the world but probably not with this twin tower design.”
Apart from the twin towers, the project includes a five-storey precast car-park linking the two buildings.  The job, which covers a total floor area of 15,000 sq m, involves shear walls, parapet walls, columns, beams, staircases and hollowcore slabs. The project is in the design stage and BPC aims to finish its work by January 2009.
Commenting about the technique, the spokesman says: “Generally, most high-rise precast buildings are designed such that the columns carry vertical gravity loads and the shear wall around lift shaft carry the lateral loads due to either wind or seismic loads. All the connections between columns and beams are designed as pin connections, whereas the shear wall reinforcement is continued from wall to wall. In some cases, a hybrid method of wall and connection between column beams are designed to support lateral loads. Though these methods are not economical, they are carried out in many instances to satisfy the architects’ requirements. 
“The reinforcement is anchored to the foundation to stabilise the buildings.”
The designs are based either on British or American standards and structural software is used by BPC to analyse the structural requirements.  
The 18-storey precast building that BPC is working on will be a precast office complex located in the Diplomatic Area. The company's scope of works includes design, supply, delivery and erection of 3,110 sq m of 300 and 250-mm-thick shear walls; 410 m of columns in various sections; 1,890 m of precast beams in various sections; 700 m of precast pre-stressed beams in various sections;   610 sq m of 150-mm hollowcore slabs (HCS), 1,330 sq m of 200-mm HCS and 5,220 sq m of 240-mm HCS as well as staircases comprising 72 landings and 72 flights.
Because of its location in thecongested Diplomatic Area, erection is only possible during nighttime, he says emphasising that the client opted for the precast building system on account of the speed that it offers and the smoothness of the finish compared to in-situ construction.
Commenting on the status of the project, the spokesman says: “Ground work has already commenced on the project which is scheduled for completion by mid-2008.”

Innovation
BPC is known for innovative precast solutions and has introduced a novel concept for precast wet rooms for buildings.
The wet room solution is a customised high-quality unit produced under factory-controlled conditions. The units can be designed and produced as per customer requirements with regards to dimensions, MEP (mechanical, electrical and plumbing) connections and openings for doors.
“This ensures that all the opening remains the same and accuracy is maintained, allowing procurement of MEP parts to take place much earlier, thus offering savings on total project cost,” the spokesman points out.
After completion, the units can easily be lifted into the building and the final finishing completed. If required by the client, BPC can also undertake the finishing works before the units are erected in the building. saving further time and cost. BPC offers heating in the floor – placed just beneath the last layer of the concrete – at a nominal additional cost, he says.
The unit can be supplied as standalone or added into the building, system and can be alternately used as pantry or filing rooms, data storage (servers) areas, walk-in cabinets or kitchenettes.

Hollowcore slabs
Hollowcore slabs continue to be BPC’s major products. With its wide range of products including 150, 200, 265, 320, 400 and 500-mm slabs, the company continues to be the biggest supplier of hollowcore slabs in the region, the spokesman claims.
BPC has also started supplying 400 and 500 mm slabs to Saudi Arabia, where one big order is under execution.