Fracture–fracture interaction during grouting

Sealing of self-supporting underground constructions is often done with grouting or pre-grouting, most often with cementitious grouts. In order to achieve sufficient sealing, fine fractures must be penetrated long distances before the grout hardens. This is achieved with high injection pressures that rivals the in situ stress normal to the fractures. In this paper, the interaction of parallel fractures during high pressure grouting is modelled and the influence of the resulting dilation is discussed. Both linear and non-linear fracture stiffness is used in the modelling.