Balvac conducted essential bearing adjustments on the M60 Barton Bridge, significantly alleviating stress on the bridge deck and extending its lifespan for years to come.
Originally constructed in the 1960’s and then widened in the 1980’s, the M60 Barton Bridge was sat on various foundation types resulting in differential movement, putting unwanted strain on parts of the structure.
Appointed as principal contractor by National Highways, Balvac delivered critical bearing adjustment works to the Bridge to reduce the strain on the existing structure.
Through Early Contractor Involvement (ECI) with National Highways and their designers, Balvac ensured buildability of the scheme, developing the various temporary works designs and related methodologies, prior to mobilising to site to successfully deliver the project.
M60 Barton Bridge, Greater Manchester
High precision bearing adjustment
The primary objective of the project was to lower the outer bearings by 0.5mm and 2.5mm respectively to relieve the stress in the bridge deck caused by the differential movement of the foundations, whilst maintaining operation of the six-lane motorway above. The secondary objective was to create an arrangement to allow for future adjustments whilst requiring minimal construction activity.
The adjustment works included removal of the grout bed beneath the bearings, allowing them to be lowered to within an accuracy of 0.5mm. Shims were installed to facilitate future adjustment more easily, and finally, the bearings were cleaned and painted to extend their life to next maintenance.
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week delivery
bearing adjustment
Key activities were delivered at night with traffic management lane closures in place, allowing live loading to be removed from the external girders. Throughout duration of the project the permanent structure was monitored for strain and movement. Engineering controls were implemented at each stage of the work with clear hold points for designer sign off. The designers attended site for all the key activities to ensure that immediate decisions could be made to ensure specification compliance.
Bespoke jacks
To facilitate the bearing adjustment, the load from the bridge deck was transferred by bespoke temporary jacks into the bearing plinths on the pier tops. There were concerns of bursting forces on the existing bearing plinth at the western end of the pier due to its height. To combat this, Balvac designed and installed a reinforced concrete strengthening detail to withstand the expected loads of the temporary jacks.
Scaffold access from ground level to the 30m high pier tops was installed and the scaffold was stiffened to allow handling of heavy equipment including the temporary jacks, which were lifted onto the platform using a designed hoist and rail system.
Highly Commended in the Constructability Category at the ICE Northwest Awards 2024
Specialist structural monitoring
Our team of experts used technology to ensure accurate data was available to the permanent works designer. The bridge had strain gauges installed on the deck and internal and external faces of the steel beams to monitor movement of the structure during the works. Linear Variable Differential Transformers (LVDT’s) were also installed at various locations to measure lift, lowering, weight and settlement of the deck structure when the load was transferred back into the existing bearings.
The project was successfully completed on time in November 2023 and was Highly Commended in the Constructability Category at the ICE Northwest Awards 2024.