Prices of reinforcement steel bars are critical to the cost of a construction project. The bars are used with concrete in civil engineering structures to create structures that are concrete reinforced like beams columns and slabs. Getting the best prices for this important construction material will have an overall impact on the cost of a construction project.
Back in 2017, Kenya followed the likes of Uganda, in banning the use of twisted bars for concrete reinforcement in construction. This was attributed to new engineering findings that had triggered reservations over the structural properties of twisted bars that make them not the best candidates for concrete reinforcement. Instead, just like many other countries in the region; Kenya resolved that only ribbed steel bars shall be manufactured and offered for sale in the country.
A ribbed steel bar is a type of deformed, high strength steel that is manufactured by controlled cold twisting of hot rolled bar. This bar has projections on its surface known as ribs hence the name Ribbed Steel Bar. They vary in sizes, ranging from 8 mm to 40 mm wide. These bars possess certain characteristics that make them preferable to twisted bars in reinforcement of concrete.
High-yield ribbed bars have minimum guaranteed yield stress of 420n/mm2, tensile strength of 500n/mm2 and a percentage elongation of 10%. Accordingly, 420n/mm2 is generally used in design as the characteristic value for the yield strength of high-yield ribbed bars.
Prices of reinforcement bars in Kenya
Structural properties is not the only reason ribbed reinforcement bars were preferred to twisted bars; cost saving was another factor. Apart from being able to bend through 180 degrees without a crack or fracture of any form, their structural properties makes it possible for them to be welded by electric flash such as arc welding and butt welding. These bars boast of excellent bonding properties than ordinary twisted bars hence the end hooks are unnecessary. Therefore, their use cuts the cost of reinforcement up to 30 to 40% hence they are very economical.
A survey of various hardware stores in Nairobi shows that despite the availability of different brands in the market including Apex, Doshi, Tononoka, Accurate etc., the prices of reinforcement steel bars is entirely based on a willing buyer willing seller on the different sizes of the rebars. The different sizes are denoted as D8, D10, D12 and D16 (D standing for diameter). D8 prices range from 450-500 Kenya shillings, D10 650-700 Kenya shillings, D12 900-950 Kenya shillings while D16 1600-1650 Kenya shillings; all 40 feet long, with Apex being the most popular brand.