Polymer Smart Materials & Technologies for Road Construction
15 July 2019
Africa is a continent with a population of 1,317 billion just lagging behind India’s 1.350 billion. Trade between Africa and India has increased eight-fold from $7.2bn in 2001 to $59.9bn in 2017. GDP growth for the continent is forecast to accelerate to 4 percent this year, up from an estimated 3.5 percent in 2018, making it the fastest-growing region in the world after Asia, according to the African Development Bank. Infrastructure development is a key driver for progress across the African continent and a critical enabler for productivity and sustainable economic growth.
Rising costs of Road Construction
After eliminating inflationary factors, statistics show a perpetual increase in road construction costs. The reasons for cost increase in developing markets, including India, are numerous. Depreciation of developing market currency has resulted in higher costs of imported plant, fuel and bitumen. These costs represent about 50 percent of the overall cost of a road-construction project.
Why African countries are embracing New Road Technologies
Many African countries have embraced new road designs and construction technologies to speed up construction time and reduce costs, without compromising quality standards. They are opting for Smart Materials to offset the increasing cost of road construction.
After two years of trials and tests using Smart Materials for road stabilization and sealing, the Ghana Highway Authorities have authorized the purchase of 122 kms of Smart Materials for the state of Kwabre by Hon. Nan Osei Asibey Bonsu. A further 400 kms of projects specifying the use of Smart Materials is being processed in other provinces, according to Ghana Highway Authorities.
Democratic Republic of the Congo (April 2019) – a delegation of VIPs visits Polyroads head office in Johannesburg, South Africa, and confirms that five years of testing in the mineral rich country has paid off and that the Government of newly appointed President Felix Tshisekedi is ready to fast forward infrastructure development, the first criteria being connectivity of villages to the main arterial roads. Polyroads signs a MoU to supply Smart Material products for 2000 kms of roads.
Road Design using Smart Materials
Smart Materials are high-tech products that are specifically manufactured for road construction. They are developed and manufactured in South Africa by Polymer Pavements (Pty) Ltd. The company is represented in India by Kaveri Ultra Polymers Pvt. Ltd.
A secialized binder SoilTech Mk. III is used to bind most in situ materials, thereby reducing the amount of imported materials normally required from quarries or borrow-pits. SoilTech Mk. III stabilized materials develop very high elastic-modulus properties, which enables the road-layers to carry greater loads without deformation or failure.
On the other hand, conventional road construction designs are based on categorized materials, with certain specified structural strengths, placed in layers on top of each other, with one layer then being stabilized with cement or lime. The stabilized section is then covered with a 150 mm layer of WMM. Finally, a bituminous carpet is applied over the WMM layer.
Benefits of Smart Material
Reduced importation of aggregate
Environmentally less impact
Reduced costs – diesel, plant wear & tear
Greater binding (CBR & UCS)
High elastic modulus – road longevity
Nano-polymer migration from the stabilized base-layer into the sub-base. One layer stabilization results in two layers becoming stabilized.