Technical assistance from Cerema to make safe a link road
In 2015, the Terre Rouge-Verdun dual carriageway fell victim to a very deep landslide (25m deep in places) that required a diversion to be put into place. The Terre Rouge-Verdun link road is a major highway in Mauritius.
After a number of appraisals by international companies – ARQ-international (South Africa) and the Korean Expressway Corporation – Cerema teamed up with IFSTTAR in April 2018 to develop a unique safety solution.
The solution consists of riveting the unstable section of the landslide in place, using two lines of piles plunged to a depth of 26m.
This required 180 piles planted to a depth of 26m, stretching for a distance of 5km. 200,000 tonnes of material had to be transported to carry out the work.
As part of the project, the Road Development Authority asked Cerema to provide technical assistance in delivering this one-of-a-kind safety project to completion. The assistance provided by Cerema included establishing guidelines for the safety project, assessing construction procedures, outlining research to optimise the project and make it more reliable, as well as occasional interventions on-site to ensure that work was proceeding smoothly.
The road will soon reopen
This occasional monitoring was accompanied by continuing supervision by the Road Development Authority, supported by experts from the Korean Expressway Corporation.
The most recent project carried out by Cerema’s soil mechanics specialists resulted in a meeting with Mr. Nando Bodha, minister for public infrastructure, on 2 February 2019. The meeting took place on-site and was attended by the press and two contractors (Transinvest and Sinohydro).
At the time of writing, almost all of the piles have been installed, which should enable filling of the road to be completed. Weather permitting, the Terre Rouge-Verdun link road will be open for traffic in late May 2019.
Learn more
The 2015 landslide got a lot of coverage in the Mauritian press, which then followed progress of work to repair this stretch of road that links two major cities.
Both the government and the local community are eager to see the 300m stretch of road reopened.
Sonic echo testing of piles, a Cerema speciality
The soil mechanics team is also a specialist in sonic echo tests for piles: Guillaume Barde, an engineer and external soil mechanics inspector at Cerema Mediterranean tells us about Cerema’s sonic echo testing for piles, using tools developed in-house, like AVSP.