Many people use the term “Chemical Grouting” to refer to any grouting technique that is performed with chemical grouts. However, this can be confusing due to the large number of chemical grouts available and the numerous grouting techniques for which they can be utilized. Generally, chemical grouts may be applicable for any type of grouting technique (structural, permeation, consolidation). The decision to use a chemical grout should be based on the advantages of the chemical grout over cementitious grouts, as the material cost is generally higher. Common types of chemical grouts and typical applications follow:
There are a large number of polyurethane grouts on the market, each of which has specific properties which have been designed to address various situations associated with their intended use. However, polyurethane’s greatest advantage is a short set time (on the order of seconds). This, along with other characteristics, often makes it the preferred choice when performing water cutoff grouting. It is often used to seal off rock faces, concrete, or other leaking structures. Additionally, polyurethane is used in permeation grouting to provide bearing capacity improvements, in structural applications, or to fill large voids (due to some formulations expansive characteristics).
Epoxy resins are almost exclusively used for structural grouting. The advantages offered are high strength and bonding capabilities. In grouting applications,epoxy resins are most often used to repair cracks in concrete or to fill other small spaces in structures where strength is required.