Sarens Supports Accelerated Bridge Replacement on A41 Motorway in Chambéry
30 Second Takeaway
Sarens has successfully supported the renovation of two bridges on the A41 motorway in Chambéry, France, a critical transport corridor carrying more than 50,000 vehicles per day. Using Accelerated Bridge Construction (ABC) techniques and 96 axle lines of SPMTs, the company completed the removal and installation of the heavy bridge structures within a tightly controlled two-day road closure.
Improving Traffic Flow on a Critical Corridor
The bridge renovation project forms part of a broader regional strategy to reduce congestion where traffic from the A43/A41 motorway and the Voie Rapide Urbaine (RN201) converges. The two ageing bridges had reached the end of their service life and required full replacement to maintain safety and long-term traffic capacity.
Each of the new bridge structures weighs 550 tonnes, while the existing bridges removed during the operation weighed 615 tonnes each. To carry out the works safely, traffic on one of Chambéry’s busiest roads was fully closed for a 48-hour period, with diversion plans implemented in advance to minimise disruption.
Heavy Transport and SPMT Operations
Sarens was responsible for:
Transporting the newly assembled bridge structures from an offsite assembly area approximately one kilometre from the motorway
Removing and transporting the existing bridge structures
Positioning the new bridges within the limited closure window
To execute the operation, Sarens mobilised:
Four SPMT configurations, each comprising 24 axle lines
A total of 96 axle lines
Custom steel support structures designed specifically for the bridge geometries
Two SPMT sets were dedicated to dismantling and removing the existing bridges, while the remaining two sets handled the transport and installation of the new units.
Accelerated Bridge Construction Method
The project was carried out using the Accelerated Bridge Construction (ABC) method. This approach involved:
Pre-assembling the new bridges offsite
Transporting the completed structures to the motorway
Rapid removal of the old bridges
Immediate installation of the new bridges once traffic was fully closed
The SPMTs had to navigate local roads and a car park before reaching the motorway, requiring detailed route planning and precise coordination. Once the work zone was secured, the existing bridges were removed, the new structures positioned, and the dismantled units transported back to the original yard.
Managing Complexity Under Tight Time Constraints
The operation presented several challenges, including:
Extreme bridge size and weight
Limited clearances along transport routes
Strict safety and traffic management requirements
A narrow two-day execution window
Despite these constraints, the works were completed safely and within schedule.
Tom Jonckers, Project Manager at Sarens, said:
“Once again, our team has demonstrated high technical and professional expertise and a strong commitment to meeting the established deadlines. The coordination effort was essential to ensure the project was completed safely, on time, and with minimal impact on the surrounding area.”
About Sarens
Sarens is a global leader in engineered heavy lifting, heavy transport and project logistics, supporting infrastructure, energy and industrial projects worldwide. With extensive experience in SPMT operations and Accelerated Bridge Construction, Sarens delivers complex operations safely and efficiently in highly constrained environments.
Visit website: https://www.sarens.com
Frequently Asked Questions
Where did the bridge replacement take place?
On the A41 motorway in Chambéry, France.
How many vehicles use this section of road daily?
More than 50,000 vehicles per day.
How heavy were the bridge structures?
The new bridges weigh 550 tonnes each, while the removed bridges weighed 615 tonnes each.
What transport equipment was used?
Four 24-axle line SPMT sets, totalling 96 axle lines, with custom steel supports.
Why was Accelerated Bridge Construction used?
To minimise traffic disruption by reducing on-site construction time and completing the operation within a short road closure window.
