Slag aggregates used in Asphalt


“We have provided The London Borough of Bromley with a sustainable road solution, using a combination of steel slag aggregate to replace virgin aggregates and warm mix asphalt. This supports the London Borough of Bromley’s commitment to the use sustainable materials.”

Chris Moore, managing director JB Riney

The binder course was to be supplied as a Warm Mix Asphalt and the ULTIPAVE used steel slag aggregate. Steel Slag aggregate is a secondary aggregate produced by the steel industry. An ideal aggregate for base, binder and surface course asphalt products. The strength and alkaline nature of steel slag also make it an ideal material for use in asphalt giving extended life to the pavement design and superior binder adhesion.


The shorter curing time of Warm Mix Asphalt enabled Riney to plane off, lay the binder and overlay the surface course in one shift. This enabled the road to be opened in just one day as opposed to the two-day operation normally associated with two-layer construction. By halving the programme, disruption to road users was minimized and associated costs, such as traffic management reduced.

The asphalt used to surface Hawthorne Road helped The London Borough of Bromley demonstrate its commitment to reduce CO2 emissions across its highways maintenance programme. The Warm Mix Asphalt reduced on site fumes by approximately 80 percent helping to achieve cleaner air targets in the capital and offering public health benefits. We delivered an innovative product which allowed Riney to exceed normal outputs and reduce the programme saving time and money.

The London Borough of Bromley has committed to using Warm Mix Asphalt on future schemes

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