September 5th, 2022
Micropiling works on the Pont de Pierre bridge in Bordeaux
Nearly 20 years after a project to reinforce the bridges first piers, Soletanche Bachy France (the consortium’s lead contractor with Sixense Monitoring) was awarded the micropile test framework contract by Bordeaux Métropole and its engineer BG Ingénierie.
The purpose of this test (framework contract renewable once) is to prepare future for underpinning work on piers P7 to P16 using micropiles, scheduled for 2024.
This will involve conducting two types of tests:
- Construction of two instrumented structural micropiles, via a central pier from the bridge deck, including 12 months’ monitoring of the micropiles and the bridge.
- Performance of a compression loading test conducted until failure on an instrumented micropile on the right bank. These micropiles are due to be installed using the same techniques as the structure’s future micropiles.
Group’s technical synergies for a bridge project
To win this very technical project, given the sensitivity of the structure, the technical issues and the uninterrupted operation of the tram, the local branch called on the Group’s experts to identify the most appropriate processes.
The particular suitability of the Hi’drill® drilling process to the project’s technical constraints (high inertia micropiles 40m deep, passing successively through reinforced concrete, a void, masonry, wood, alluvium and rough marl), associated with the latest instrumentation technologies proposed by Sixense, ticked all the boxes contained in the specifications.
From the start of August, teams from the France Sud agency were “on deck” to install the structural micropiles, before moving to the right bank for the failure load test. The work is due to be completed by mid-October.
