The country’s first ‘steel slag road’ has come up in Surat, promising a huge potential to reduce the demand for aggregates in road construction. The successful implementation of the 1.2 km six-lane connectivity stretch of the Hazira Port will also pave the way for utilisation of huge mounds of steel slag lying as waste across the country. Aggregates are inert granular materials such as sand, gravel and crushed stone used in road construction.
This research project under the steel ministry was sponsored by ArcelorMittal Nippon Steel under the technical guidance of the Central Road Research Institute. This stretch has been built by substituting natural aggregates with 100% processed steel slag aggregates in all layers of bituminous pavement.
Considering its higher strength, the thickness of the road has also been reduced by 30%.
Three other major steel majors — Tata Steel, JSW Steel and Rashtriya Ispat — are participating as industrial partners to accomplish the steel slag utilisation in road construction.
“Around 1,000-1,200 heavy commercial vehicles are using the road per day for the last one year and still it is performing well on different serviceability parameters. Around one lakh tonnes of processed steel slag aggregates have been utilised in this project. We will soon come up with guidelines for usage of processed steel slag in road and highway construction,” said Satish Pandey, principal scientist at CSIR-CRRI.
Annually, nearly 18.5 million tonnes (MTs) of steel slag is generated from various integrated steel plants. Only in Vizag, around 60MT of steel slag is lying unused.
Utilisation of steel slag aggregates as a substitute of natural aggregate in road construction will reduce the unsustainable quarrying and mining of natural aggregates.
Highways projects in several states are now getting delayed due to shortage of aggregates and other raw materials.