Etude régionale par éléments finis d'une nappe libre située dans les craies du Crétacé en Belgique

in Revue des Sciences de l'Eau = Journal of Water Science (1991), 4

Water table aquifers and finite element method: analysis and presentation of a case study

in Computational Modelling of Free and Moving Boundary Problems, vol. 1, Fluid Flow (1991)

The mean features and characteristics of the 3D FEM in the central area of Shanghai

in Proceedings of the Int. Conf. on Modelling Groundwater flow and pollution, Nanjing (1991)

Modèles mathématiques en hydrogéologie et paramétrisation

in Annales de la Société Géologique de Belgique (1991), 113(2), 217-229

Engineering Geology Conditions of the Central Area of Shanghai : Preparation of the data for subsidence modelling

in Sixth International Congress of the International Association of Engineering Geology, Amsterdam (1990, August)

Influence of the hydrodynamic coupling on the results of an oedometric finite element model

in ModelCARE 90, Calibration and Reliability in Groundwater modelling: volme of poster papers (1990)

Applications hydrogéologiques d'un modèle mathématique 2D par différences finies sur Personal Computer

in Tribune de l'Eau (La) (1989), 41(6), 42-46

Gravimetric exploration applied to the detection of faults in the area of Mol - Turnhout (Belgium)

in Annales de la Société Géologique de Belgique (1989), 112(2), 431-441

A gravimetrical exploration has been realized in the area of Mol and Turnhout (province of Antwerp, Belgium) to localize steep dipping faults in the Paleozoic bed rock and the Meso- to Cenozoic overburden ... [more ▼]

A gravimetrical exploration has been realized in the area of Mol and Turnhout (province of Antwerp, Belgium) to localize steep dipping faults in the Paleozoic bed rock and the Meso- to Cenozoic overburden. With a 600 to 1000m thick overburden consisting of sand and clay, 10m high steps in the bed rock result in significant gravimetrical anomalies. The interpretation is based upon comparison with theoretical anomalies computed for various density contrasts and depths. After the classical corrections, the Bouguer anomaly has been smoothed and horizontal derivatives computed to reduce the effect of shallow heterogeneities and regional gradients. The results confirm the presence of several faults already detected by other methods and enable a more accurate positionning. [less ▲]

Finite difference and finite element modelling of an aquifer in Cretaceous chalk

in Proceedings of the sixth International Conference on Numerical Methods in Geomechanics (1988, April)

Finite elements modelling of a large water table aquifer in transient conditions

in Advances in Water Resources (1988), 11(2), 58-66

A chalky aquifer located near Liege (Belgium), is recharged by infiltration through the overlying loess. Wells and collecting tunnels produce a daily flow of 60OO0m a out of this aquifer when ... [more ▼]

A chalky aquifer located near Liege (Belgium), is recharged by infiltration through the overlying loess. Wells and collecting tunnels produce a daily flow of 60OO0m a out of this aquifer when hydrogeological balances have shown that an average yield of 100 0OO m a/day should be possible. Finite element modelling has been developed to foresee the evolution of the water table to get some additional information especially about the main drainage axis. The transient flow constitutive laws are recalled in confined and unconfined aquifers. A new law is proposed to model the water table surface in transient conditions and with a fixed meshing network. Using the local flow equilibrium and the virtual power principle, the FEM formulation is set up. The time integration and the iteration technique are shortly discussed. The 3D discretization and the modelling of the entire aquifer has been realized. The problem requires about 3600 DOF and 2670 8-nodes isoparametric brick finite elements. The modelling has been quite delicate because of the geometric complexity of the different geological layers. This complexity justifies fully the use of the finite element method; there is indeed a great diversity of geological characteristics and the range of the different permeabilities is very wide. Sensitivity of the model to permeabilities and storage coefficient variations has been studied and various numerical problems have been notified. The calibration procedure is described in its main steps, and the most significant results are presented. [less ▲]