Experiences With Real Time Grouting Control Method

Magazine article, 2010

In the paper the concept of “Real Time Grouting Control Method” is described in order to calculate the grout penetration and to control grouting in real time by applying developed theories for grout spread. The stop criterion can with this method be related to achieved grout spread such as the fact that grouting is completed when the grout penetration for the smallest fracture that has to be sealed is above a certain minimum value (target value) or before the grout penetration for the largest fracture aperture reaches a certain maximum value (limiting value). It might also be possible by following the ongoing grouting minute by minute to predict the course of the grout flow and spread and also analyze the risk for uplift and jacking. These issues will also be discussed in the paper. Verification of the “Real Time Grouting Control Method”, with field data from four tunnel projects in Sweden is presented in the paper. The calculated flow dimensionality, the calculated fracture apertures and the calculated grout flows were quite close to those measured. This indicates that the “Real Time Grouting Control Method” may be applicable to real grouting design and control.