A465 Heads of the Valleys, Section 2 Gilwern to Brynmawr
Products: Hanson aggregates and concrete containing Regen GGBS
Client: Costain
Volume supplied: 200,000 tonnes of locally sourced aggregate; 30,000m3 concrete
Overview
Early contractor involvement and pre-programming of work has helped Hanson effectively deliver the concrete requirements for the A465 Heads of the Valleys road improvement scheme, Section 2 Gilwern to Brynmawr.
Project description
The A465 project involves converting 8.1km of the road, between the Glanbaiden junction at Gilwern and the Brynmawr roundabout, to two lanes in each direction, including the construction of 16 major concrete structures along the route.
Through early engagement and collaboration with the site team, Hanson was able to offer technical support and practical advice for the concrete mix designs for these structures. This open approach, working with Costain and its designer CH2M/Atkins JV, ensured that agreeing the final mixes was a seamless process.
All of the concrete mixes have been designed to incorporate Regen GGBS (ground granulated blastfurnace slag) from Hanson’s nearby Port Talbot works. Regen is used to replace a proportion of the cement content and reduce the CO2 emissions associated with the concrete.
It is a by-product of iron-making and its manufacture requires much less energy and produces around one tenth of the CO2 emissions of Portland cement. It also requires no mineral extraction and prevents thousands of tonnes of waste being disposed to landfill.
A structured, pre-contract meeting ensured the Hanson concrete and aggregate technical, operational and delivery teams were fully engaged with the Costain project delivery team, understanding the scheme’s key requirements.
Flexible material deliveries were important to the project and the travelling public. As a result, Hanson minimised disruption by completing the majority of the large concrete pours out of hours at weekends.
Following an initial site meeting, clear lines of communication were established. This, along with a structured approach to regular site meetings to agree forward demand programming, technical compliance and site logistics, ensured the successful delivery of the project.