Mainmark delivered a lightweight engineered fill solution for Network Rail as part of a bridge remediation programme on Ashley Road in Hale, near Manchester. The project involved reducing the load acting on a bridge abutment by replacing existing material beneath the roadway with lightweight Porofoam 900, helping facilitate critical infrastructure repairs while maintaining programme efficiency.

Addressing Load Reduction on Network Rail Bridge

A highway bridge carrying a public road maintained by Trafford Council over a railway line was experiencing issues within one of its abutments. As part of the wider remediation strategy, the loading acting on the structure needed to be reduced to support long-term asset performance.

The programme required:

• Excavation beneath the existing road structure

• Removal and disposal of excavated material

• Installation of a lightweight engineered fill solution

• Careful delivery within a live rail environment

• Reinstatement of the roadway following completion of works

The solution also needed to align with the design specifications developed for the project.

The Solution

Mainmark delivered a complete package of works, including excavation, disposal, lightweight fill installation and road reinstatement.

Using 45.5m³ of Porofoam 900, installed across four separate pours, the team replaced heavier materials beneath the roadway with a significantly lighter engineered alternative. The works included:

• Excavation and disposal of existing material

• Installation of lightweight Porofoam 900

• Reinstatement of the road structure to binder course level

Porofoam 900 was selected for its lightweight properties and ability to significantly reduce loading compared with conventional fill materials, while providing a typical compressive strength of 5.0N/mm² after 28 days.

The Results

Mainmark successfully completed the works in accordance with project requirements, providing Network Rail with a lightweight engineered fill solution that contributed to the reduction of loading on the bridge abutment and supported the wider remediation programme.

Project Outcomes

• Reduced structural load acting on the bridge abutment

• Delivered a lightweight alternative to traditional backfill materials

• Supported a wider bridge remediation programme

• Completed excavation, fill placement and reinstatement as one coordinated package

• Enabled critical infrastructure repairs to progress efficiently

Client Feedback

"Now that all works have been completed on site, I would like to thank you and your team for your efforts. The project has been delivered to a high standard and ahead of programme, which is greatly appreciated."

Dave Eccles, Network Rail

Key Benefits

Reduced Load on Critical Infrastructure

Replacing conventional fill with lightweight engineered material reduced the deadload acting on the bridge abutment, supporting the project's remediation objectives.

Single-Source Delivery

Mainmark provided excavation, disposal, lightweight fill installation and reinstatement as part of one coordinated solution, reducing programme complexity.

Rail Environment Experience

Works were delivered within an operational rail environment, helping ensure safe and efficient project execution.

Engineered Alternative to Traditional Backfill

Porofoam 900 provided a lightweight solution capable of achieving substantial weight reduction while delivering the performance required by the project design.