Geo-materials Environment & Planning Laboratory (LGEA)

The team's objective is to study transfers through soils and the unsaturated zone of the aquifer. The difficulties in modeling these transfers stem from the characterization of the various non-linear relationships between permeability, capillary capacity, macro-dispersion and water content and/or temperature, as well as the parameters involved in all these relationships. Research will focus on two different approaches: the development of new numerical methods for monitoring state variables (water content - pressure). And secondly, to develop a device designed to measure the essential physical characteristic of unsaturated flow problems: capillary conductivity, analogous to the permeability coefficient of saturated flow. The main problems involving soils or rocks under partial saturation are :

 - The foundations of many surface constructions are based on unsaturated soils.

 - Slope and slope failures are often linked to changes in the degree of saturation.

 - In countries with arid or semi-arid climates, soils are often unsaturated.

The research team is currently working on adding glass powder to concrete to replace a yet-to-be-defined quantity of cement. This is an experimental project, and the use of glass powder in concrete is a sustainable development technique, since the powder will be recovered by crushing glass waste discarded in the environment. In addition, the addition of glass powder improves the mechanical properties of concrete and reduces the use of cement. The latter, in addition to producing dust, generates greenhouse gas (GHG) emissions, mainly CO2, which in turn pollutes the environment (one tonne of cement produces around one tonne of GHG). So, reducing cement production, which lowers costs, has environmental, technological and economic aspects. But the question is, how does this powder added to concrete improve or at least maintain the mechanical properties of concrete despite the reduction in the quantity of cement? The aim of this work is to determine the quantity of cement that can be replaced by glass powder to improve or at least maintain the same properties of concrete,

The "Hydrotechnical Engineering" team is generally concerned with the design and calculation of civil engineering structures on the sea coast or in rivers. These include various types of quay (weighted, caisson, pile or sheet-pile), harbor protection dikes (natural or artificial rockfill, or solid concrete) and dams (earth, rockfill or concrete). More specifically, the team is interested in studying the dynamic interaction of these structures with the contact soil. Seismic activity in Algeria does not spare marine and river infrastructure structures (construction and rehabilitation). The toll is all the greater when the seismic hazard is combined with the fact that these structures are built in a high seismic zone (north of the country) or on soil with poor characteristics (presence of liquefiable layers, low bearing capacity, compressibility, etc.). In such circumstances, it is advisable to search for the right soil at depth, thus favoring the use of deep foundations (sheet piling, piles, etc.).