Course of Underground hydraulics(Ourse and Solved exercises)

Abstract

The course on groundwater hydraulics presents the theoretical and practical foundations of water movement in soils. The first part covers the general characteristics of soils, emphasizing the importance of water in the soil, whether free, capillary, hygroscopic, or structural. Essential soil properties, such as porosity, effective porosity, void ratio, density, and specific weight, help in understanding the soil’s capacity to store and transmit water. The study of aquifers, whether unconfined or confined, highlights the role of effective porosity, storage coefficient, hydraulic conductivity, transmissivity, and diffusivity in the behavior of groundwater systems.

The second part focuses on the physical and theoretical bases of groundwater hydraulics. Soils and fractured rocks are considered natural porous media, while structures like dams represent artificial media. Concepts such as homogeneity, isotropy, and anisotropy are crucial for understanding water flow, since most natural media exhibit anisotropy. Water movement relies on several assumptions, including soil saturation and incompressibility of grains and water. Darcy’s law forms the foundation for flow modeling, and experiments with constant or variable-head permeameters allow measurement of permeability. The concepts of flux and the continuity condition ensure that the volume of water entering a saturated soil volume equals the volume leaving it.

The third part addresses practical problems, such as well hydraulics and steady or transient flows. The Dupuit and Thiem formulas allow the calculation of transmissivity, storage coefficient, discharge, and water velocity in aquifers. The study of flows in isotropic and anisotropic media, along with the electrical analogy method, facilitates the analysis of groundwater flow networks. Finally, solved exercises illustrate the application of these concepts to concrete problems, such as calculating porosity, density, storage coefficients, or soil granulometry. Overall, the course provides students with the fundamental knowledge needed to understand and predict the behavior of groundwater in various hydraulic contexts.