Boardwalk Project on the Banks of Highway A6A in Gentilly (France)

Gentilly, Val de Marne (94)
Île-de-France, France

Date : February to June 2016

Dealer : Techno Pieux Picardie

Engineers :

Guillaume Blestel (Techno Pieux)
Stéphane De Franssu (Techno Pieux)

Partners :

Architecte P.Bertrand
Agence L’Anton paysagiste
J. Anglade BET bois
BESIconseil
A.Paquet

Project Description

The goal of the project is to design a helical pier foundation, using the data obtained from soil reports and engineering calculations. The foundation must support the determined loads and work with the configuration of the slope. In addition to this, the installation must be done without interrupting traffic on Highway A6A.

The boardwalk structure is 180 meters long by 4 meters wide. One half of the boardwalk is suspended approximately two (2) meters above the banks of Highway A6A. The Techno Metal Post engineering team has determined the proper model of piers to install, based on the load requirements and soil characteristics.

A noise barrier to reduce the traffic noise is integrated into the structure of the boardwalk. The foundation must be able to support all the oak wood structure and the siding material.

The Proposed Solution by Techno Metal Post

Based on the expertise of the company, Techno Metal Post was able to complete the installation of piers in 4 weeks. The specialized installation equipment EM-1 and ET-1 were used on this inclined slope area. The 112 piers used are Model P4 HD: 4" x 0.313." [ 101.6mm x 8.0mm ] installed at depths of up to 7.5 meters. Three (3) Techno Metal Post certified installers completed the installation.

Considering the geotechnical investigation and the results of a load test, Techno Metal Post was able to propose a unique solution to support this structure in challenging conditions. Because of the specialized equipment used, the piers were installed from the top of the bank. This approach allowed traffic to run normally throughout the duration of the project.

The structure of the boardwalk was prefabricated in sections of 3 meters. The pier positioning was very important within a 5 mm tolerance. A crane was used to put each section on the helical pier foundation.