Following the initial design which was carried out by Barry transportation and the main JV contractor, Roadstone was contracted to construct the pavement structure. This required both the Roadstone R&D team and Contracts division to carry out extensive mix design and trials to ensure compliance with the overall pavement design.
A brief outline of the design parameters is as follows.
The Mainline incorporates a 40-year design life
Pavement to flexible composite design
Overall Pavement Thickness Of 340mm
In order to fulfil the needs of the client the following quantities were required.
150,000-ton Clause 804/808
175,000-ton CBGM
170,000-ton Blacktop Of which recycled materials were used.
30,000-ton is Stone Mastic Asphalt of varying PSV values depending on skid resistance requirements noted within the design documents.
Prior to the construction phase commencing significant capital expenditure was deemed necessary. Potential risks to pavement durability at the interface between carriageways and lanes was identified. If water ingress was not prevented this could affect the overall design life of the pavement structure.
Therefore following this initial assessment the following plant was procured and used.
Vogele 1083–3i with extended screed purchased specifically for N22 Contract
3 no. Bomag 161AD with intelligent compaction technology
Atlas Capco – Material Transfer Vehicle
Several pieces of ancillary plant and equipment