ABSTRACT

Any change in pore pressure (and thus also in the piezometric heads) may induce consolidation if the geological formations are compressible. Effective stress and water pressure variations at depth are explained for given drawdowns in confined and unconfined conditions. Geomechanical aspects are fully coupled to groundwater flow equations with specific storage coefficients dependent on the medium compressibility. The induced changed in hydraulic conductivity may also be expressed by a nonlinearity in the considered equations. Examples of land subsidence processes in famous “sinking cities” are given, with particular attention on Venice, The Netherlands, Bangkok, Mexico City, and Shanghai. The chapter ends with new developments in the measurement and remediation of land subsidence.