Mitigation of the effects induced by the rise of the water table around undreground structures

ABSTRACT: A finite element approach is discussed for the analysis of low-pressure injections of diluted chemical solutions in granular deposits. This technique represents, in fact, a possible provision to reduce the "natural" permeability of pervious soils and to limit the seepage flow towards underground openings that were not properly waterproofed. The grouting process is modelled as the advective-dispersive flow of a liquid containing a solute. First, an empirical law is presented for the variation of permeability with time and with the concentration of the grouting mixture. Then, the equations governing the process and their finite element formulation are discussed. Finally, the results of a series of two- and three-dimensional analyses are illustrated and some conclusions are drawn on the effectiveness of the treatment