The laboratory

The GeoEND laboratory is a research unit of the GERS department in the Gustave Eiffel University. It is located in Nantes (West of France).

Objectives, Methodology

We develop geophysical monitoring methods applied to the sub-surface and in relation to anthopogenic structures as well as methods of evaluation and non-destructive testing applied to civil engineering infrastructures. For that purpose, we carry out methodological and material developments, with the support of numerical modeling.

We aim to improve our understanding of electromagnetic, mechanical and electrical fields and our ability to model them. We use an integrated approach, which starts from the needs, identifies the relevant scientific barriers, defines the numerical and experimental modeling actions carried out in parallel in the laboratory, tests and validates the techniques developed on real sites.

For this, the team relies on equipment, part of it is unique, as well as on numerous internal, regional, national and international collaborations with both public and private institutions.

Scientific issues and application areas

Civil engineering and energy

This field is well represented in GeoEND's activities. It includes connections with the French nuclear sector (waste storage, concrete containment). It currently extends to the oil and gas sector (subsurface imaging, pipeline monitoring).

Risks

Mechanical and hydric monitoring of dikes and sea defences is a central concern (seismic ambient noise, electrical tomography monitoring) as well as the detection of potentially dangerous cavities that are difficult to detect by conventional geophysical methods.

Durability of the infrastructures

The GeoEND laboratory is involved in the development of Evaluation and Non Destructive Testing methods for the detection and localization of defects in slender structures (cable, tie rod, rail) and in the mechanical and physico-chemical characterization of concrete structures (coupling of techniques, measurement of property gradients).

Some examples of application

Detection and characterization of fractures, faults, cracks or delamination
Characterization of damages, micro-cracking of rocks (in mines and tunnels) or concrete,
High resolution characterization of soil in the vicinity of structures,
Characterization and monitoring of protection structures against flooding (river, coastline),
Detection of defects in prestressing cables and hangers,
Characterization of hydraulic and bituminous concretes.