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Case study

Fill to structure

IBAA is an extremely cost effective and there are advantages logistically when using IBAA due to the low density of the material, meaning fewer vehicle movements when compared to Primary Aggregates. 

M25 Junctions 29 – 30 widening project BPL worked closely with the client, delivery partner and consulting engineers to ensure full compliance with specifications, environmental requirements and achieving a sustainable solution for the project.

Skanska Balfour Beatty Joint Venture, working on behalf of Connect Plus and the Highways Agency.

Delivery Partner
Skanska Balfour Beatty Joint Venture

Material Requirements
40,000 tonnes of 10mm down IBAA to the following specifications: SHW 503 – Bedding and surrounding of pipes SHW 513 – Permeable backing to earth retaining structures SHW 600 – Fill to structures

Backfill to a retaining wall in 250mm thick layers compacted to end product compaction 95% of maximum dry density.

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