OPTIMUM’s unique trenchless calculation capacity proved invaluable on a recent HDD project for RTE under the Nantes ring road, near FC Nantes’ Beaujoire stadium.
RTE wanted to reduce the drill path depth of planned HDD crossings under the ring road to limit the project’s impact on nearby municipal sports facilities. Since this would increase the risk not only of drilling fluid break outs on the ring road but also settlement levels, RTE wanted to carefully evaluate the changes before validating the new profile.
OPTIMUM, which had already carried out G1 PGC and G2 PRO studies for the two drills, reworked the geotechnical model and simulated soil resistance / drilling pressure whilst also evaluating the surface settlement by finite elements, a combination that only OPTIMUM offers in France.
The calculations confirmed the feasibility of the drill path change ; RTE was able to go ahead, entrusting drilling to Groupe Gendry, which completed the project without any impact to the ring road ; mission accomplished.
