I'm looking for advice on the proper grout mix for VW piezos installed in fully grouted boreholes.
With VW piezo installations in fully grouted holes, the rule of thumb, as I've come to learn, is to mix the grout so that it mimics the strength of the surrounding formation. However, the grout also has to be pumpable, limiting it to a weight ratio of approximately 2-water, 1-cement, 0.3-bentonite. This mix results in a grout that is on the order of 50-100 psi in strength, whereas hard rock is typically thousands of psi in strength.
Do any of you think that this difference in strength could possibly lead to problems with the long term functioning of the VW piezos?
With VW piezo installations in fully grouted holes, the rule of thumb, as I've come to learn, is to mix the grout so that it mimics the strength of the surrounding formation. However, the grout also has to be pumpable, limiting it to a weight ratio of approximately 2-water, 1-cement, 0.3-bentonite. This mix results in a grout that is on the order of 50-100 psi in strength, whereas hard rock is typically thousands of psi in strength.
Do any of you think that this difference in strength could possibly lead to problems with the long term functioning of the VW piezos?