Experience with the real time grouting control method / Erfahrungen mit einer Echtzeit Kontrollmethode für das Injizieren

A new concept of "real time grouting control method" is described by which grout penetration and grouting control are made applicable in real time by applying theories for grout spread. The stop criterion with this method can be related to achieved grout spread, and grouting may be considered complete when the grout penetration for the smallest fracture to be sealed is above a predetermined target value, or before the grout penetration for the largest fracture aperture reaches a certain maximum limiting value. It might also be possible by online monitoring of the process to predict the course of the grout spread and flow and to analyse the risk of uplift and jacking. Four tunnel projects in Sweden are presented in the paper. These references indicate that the real time grouting control method may be applicable to real grouting design and control.