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Le Grand-Quevilly, France

Herrier G.,Lhoist Research and Developpement | Puiatti D.,DPST Consulting | Chevalier C.,IFSTTAR | Froumentin M.,Normandie Center | And 2 more authors.
WasserWirtschaft | Year: 2013

This paper describes the SOTREDI project, "Soil TREatment for Dikes", undertaken by Lhoist Group, a lime producer, since 2005. This project was led in partnership with research centres and universities, and presents new perspectives for the use of soils in hydraulic context. The objective was to demonstrate that soil treatment with lime, besides enhancing the materials workability, confers high levels of mechanical properties and low permeability values. Lime-treated soils also offer a reduction of piping and internal erosion hazards, and significantly increase the erosion resistance against overtopping and overflowing.

Fargier Y.,Electricite de France | Palma sLopes S.,University | Fauchard C.,Normandie Center | Francois D.,Electricite de France | Cote P.,University
Near Surface Geoscience 2012 | Year: 2012

In France, EDF (Électricité De France) is in charge of managing the large hydraulic structure stock dedicated to producing hydroelectricity. This responsability is associated with high economical and safety issues. Electrical Resistivity Imaging (ERI) is being widely used on earth embankment dikes, either for extensive survey of large sections (a few km) or for higher resolution surveys on shorter sections (a few 100m). However, the processing of extensive longitudinal survey with conventional 2.5D software is likely to yield image artefacts. This study aims to show that a bad management of the dike complexity in the inversion process is the origin of these artifacts. To overcome this limitation, a new inversion algorithm specially created to take into account the complex behaviour of the dike is presented. This development aims at filling the gap between more classical 2D and purely 3D approaches, by optimising a compromise between acquisition cost and model reliability. Applied to real data sets this tool supplies a new understanding of the interpretation capability of the inversion results.

Kaouane C.,Ecole Polytechnique de Montreal | Kaouane C.,Normandie Center | Chouteau M.,Ecole Polytechnique de Montreal
RILEM Bookseries | Year: 2012

Severe climatic conditions and poor methodology of maintenance and rehabilitation in Quebec make assessment survey of pavement a necessary however difficult task. In order to support prior results obtained with numerical modeling and to address optimal design of equipments, we determined physical properties of concrete, asphalt and foundation soil. These materials have been sampled from a street in the city of Montreal for which pavement had to undergo complete rehabilitation. The last complete rehabilitation of this street was done more than 30 years ago and material properties and composition were largely unknown. Before removal of pavement, we carried out a GPR survey with two distinct pairs of antennae (450MHz and 900MHz). Laboratory tests on concrete and asphalt were conducted on wet and dried samples, trying to reproduce the variability of physical properties due to changes in climatic conditions for a whole year. We measured complex dielectric constants in the range 50MHz-900MHz with a recently developed dielectric probe, and electrical resistivity using a simple laboratory system. Results show low variability of properties of asphalt depending of the saturation compared to larger variability in concrete. Finally all collected data are used as input to numerical modeling, and results compared with the survey data. © RILEM 2013.

Rosey F.,Normandie Center | Auberlet J.-M.,University Paris Est Creteil
Safety Science | Year: 2012

The analysis of the variability of vehicle trajectories can reveal important information about how situational constraints influence drivers' behaviour (e.g., lateral position and/or speed). Variability in the lateral position using a driving simulator was examined. Forty-two participants had to drive on two road environments: a 3. km straight road with a crest vertical curve (CVC) with perceptual treatments and narrowed lane width with subsequent provision of a hard shoulder, by relocation of the road markings. The results showed that, on the one hand the lateral position variability was greater when driving on the test CVC, before meeting oncoming vehicle and on the narrowed lane width; and on the other hand it was limited according to the perceptual treatment used. The lateral position variability would be a difficulty indicator of road geometry which would inform road managers of the presence of a risk zone on their road network. © 2012 Elsevier Ltd.

Auberlet J.-M.,University Paris Est Creteil | Rosey F.,Normandie Center | Anceaux F.,University of Valenciennes and HainautCambresis | Aubin S.,CER ESEO | And 3 more authors.
Accident Analysis and Prevention | Year: 2012

Our study focused on the lateral position of drivers in relation to risk on rural crest vertical curves, using a field site proposed by a local operator of the French road network (Conseil Général de Maine-et-Loire, 49). The final goal was to test one road treatment on this field site. The study consisted of three stages. The first, using driving simulators, selected two perceptual treatments (i.e.; rumble strips on both sides of the centerline and sealed shoulders) from five that were tested in order to help drivers maintain lateral control when driving on crest vertical curves. The rumble strips were installed first on the field site. The second stage was to develop a diagnostic device specifically in order to evaluate, on the field site, the impact of a perceptual treatment on the driver's performance (i.e.; lateral position). This diagnostic device was installed in the field upstream and downstream of the target crest vertical curve. The third stage was to collect the data during two periods, before and after the centerline rumble strips were installed. We then compared the results obtained in the field study with those from the driving simulator studies. The comparison showed that, as in the simulator studies, the centerline rumble strips on the crest vertical curve affected lateral positions, causing the participants to drive closer to the center of the lane. Finally, the results showed the usefulness of driving simulators in the road design process. © 2011 Elsevier Ltd. All rights reserved.

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