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FRENCH NUCLEAR POWER PLANTS FOUNDATION

J-L. COSTAZ, M. HAGHGOU E.D.F., S.E.P.T.E.N. - Lyon - France

In Revue Fran~aise de G4otechnique Nr. 41, fourth quarter 1987, 7-28.

SUMMARY

After rapid description of the studies made by E.D.F. for the choice of the nuclear sites and for determining the geotechnic data, the soil- structure interaction problems for static loadings are presenned. Settlements are calculated using a global finite element method or a method of substructure with variable spring stiffness. Comparison of measured and calculated settlement of four reactor buildings of French nuclear power plants are then presented and analysed.

Finally, development works related to the feedback experience provide an approach for the future which has to take into account laboratory and in situ test results.

STABILITY ANALYSIS OF REINFORCED SOIL STRUCTURES THROUGH A HOMOGENIZATION METHOD

P. de BUHAN, J. SALEN~ON Ecole Polytechnique - Palaiseau - France

In Revue FranGaise de G~otechnique Nr. 41, fourth quarter 1987, 29-44.

SUMMARY

The increasing use of soil reinforcement techniques in the field of geotechnical engineering, requires the elaboration of reliable as well as practical yield design procedures for reinforced soil structures. The proposed method originates from the intuitive idea that from a macroscopic point of view, reinforced soils can be regarded as homogeneous but anisotropic materials, on account of the existence of privileged orientations due to the reinforcing inclusions.

The strength criterion of such an equivalent homogeneous material can be theoretically determined starting from the strength characteristics of the reinforced soil components. Application of such a criterion, which can be explicitely formulated within the framework of a multilayered modelization for the reinforced soil, is then performed on the case of the stability analysis of some typical structures. Special concern has been given to reinforced earth structures, and it turns out that the theoretical estimations so obtained are in good agreement with experimental data. Despite some limitations which are outlined in the paper, the yield design homogenization procedure thus proposed is likely to become an appropriate design method for reinforced soil structures.

B. CAMBOU Ecole Centrale de Lyon - France