GROUTING WIDE CRACKS
IN A TROUBLE-FREE APPLICATION

AT 45 MINUTES FROM START

It is evident at 30 minutes that a still thicker mix would be accepted without clogging, so 0.5:1 is used for the third 15-minute period.

Large PLOT 045.gif - 14316 Bytes

Assume that the hole takes 18.00 cu ft of grout[ 495 litres] in this period.

This mix (0.5:1) is the thickest practical grout for this type of grouting. It is probable that thickening to it after so much cement has already been injected would cause slowing of the grout take. However this would produce very little reduction in the actual amount of cement taken. A slight buildup of pressure could be expected.

Assume you are using a grout mixer able to handle this 0.5:1 grout (such as a high-shear, high-speed mixer, as described elsewhere on this site and in the Guide). Not all mixers can handle this thick mix without the need for additives - which are outside the range of these simulations.

SUMMARY OF APPLICATION SO FAR - at 45 minutes
Permeability before grouting is more than 100 lugeons (high)
Water:cement ratio = 0.5:1. Pressure builds up to 5 psi [0.3 bars]
Total cement injected so far

It is necessary to decide what to do next. The choice is from one of the following:

  1. Let the simulation decide what to do next.
  2. Carry on grouting without change.

Or if you have already worked through the simulation and wish to return to some of the steps again, CLICK HERE.for a list of them.