E. Maranha Das Neves

Advances in Rockfill Structures

1 Rockfill Structures: The Present and the Future.- 2 Physical Characterization and Assessment of Rock Durability Through Index Properties.- 3 Rockfill Modelling.- 4 Laboratory Shear Strength Tests and the Stability of Rockfill Slopes.- 5 Laboratory Compression Tests and the Deformation of Rockfill Structures.- 6 Collapse: its Importance, Fundamentals and Modelling.- 7 Test Fills and In Situ Tests.- 8 Laboratory Testing and Quality Control of Rockfill - German Practice.- 9 Creep of Rockfill.- 10 Filters and Drains.- 11 Stress - Strain Laws and Parameter Values.- 12 Finite Element Methods for Fills and Embankment Dams.- 13 Concrete Face Rockfill Dams.- 14 Static behaviour of Earth-Rockfill dams.- 15 Dynamic Behaviour of Rockfill Dam.- 16 Monitoring and Safety Evaluation of Rockfill Dams.- 17 Principles of Rockfill Hydraulics.- 18 Through and Overflow Rockfill Dams.- 19 Specifications and Control of Natural Rockfills.- 20 Asphaltic Concrete Face Dams.- Closing Session.- List of Participants.

Numerical modelling of borehole water-inflow tests in the foundation of the Alqueva arch dam

Borehole water-inflow tests allow measurement of discharges and water pressures in isolated sections of drains and piezometric boreholes. A series of water-inflow tests and water electrical conductivity analyses were carried out in an area of the foundation of an arch dam. Detailed three-dimensional (3D) numerical models developed for the analyses of the test data in two foundation areas are presented. Results of rock mass permeability tests and areas where seepage paths cross each drain, identified with both water-inflow tests and water electrical conductivity analyses, were taken into account. Models were validated against flow rates and water pressures recorded in situ. By examining water-inflow tests using numerical models, the main flow processes are identified and quantified. Test results and conclusions drawn from the detailed 3D models were used to elaborate a global model of the foundation. The present study shows that borehole water-inflow tests add valuable information to the usual monitoring d...

Modelling collapse on rockfill dams

Abstract This paper deals with prediction of collapse settlements due to saturation of rockfill, mainly in embankment dams. After some brief considerations about the physical basis and the practical importance of the phenomenon, a research program on this subject developed in LNEC is presented. Using non linear elastic models (and adequate loading and unloading-reloading criteria) whose parameters are quantified by laboratory tests and data from a field test, it is concluded that is possible and reliable to predict collapse settlements due to saturation of rockfill embankments. As a result of a parametric study the relative importance of the different parameters in the model is analyzed.