‘GROUT’ is defined by the Concise Oxford Dictionary as ‘a thin fluid mortar for filling interstices’. ‘MORTAR’ is then defined as ‘a mixture of lime or cement, sand and water (originally made in a mortar) for joining stones or bricks’, and ‘INTERSTICE’ is further defined as ‘an intervening space, chink or crevice’.
This compound definition of grout is the one that seems to be most commonly understood in general civil engineering practice, although it is obviously about 50 years out of date. Since a "joining" function is considered for the mortar material, the property of adhesion is implicitly required. This property is apparent to any substantial degree only in the resin based mortars or grouts, which are the products which we are interested in.
Firstly, let us examine the uses to which grout is put, and then focus specifically on the design parameters for Machinery Grouts.
2. GROUT APPLICATIONS
A great deal of grout is manufactured around the world. We estimate the volume produced in Japan alone as between 30,000 and 40,000 cubic metres. That does not include all the grout or mortar which is simply mixed at a jobsite for a specific purpose, from the cement and sand available. In the relatively mature market of the US, approximately 4,000 to 5,000 cubic metres of epoxy grout is sold each year, and the inorganic market is probably 10 to 20 times larger.
Grout is used in one form or another to:
– fill the space between the facade and the rock wall of a tunnel and to seal any fissures in the rock;
– fill the space between the walls of a well and the ground or rock through which the original hole has been drilled;
– fill the space between the top of the piers and the steel base plates for bridge spans;
– fill the annular space between the prestressing rods or wires and the concrete slab of a bridge deck;
– fill the legs of an offshore platform, after it has been set in place and spudded;
– fill the annular space between gas distribution piping and the sleeve which carries the pipe under the road;
– fill the spaces between one brick and another, or between a concrete wall and the tiles stuck onto it (although we would usually probably call such a product a "mortar", it is definitely performing a grout function);
– fill the space between structural steel columns and the pier footings on which they are set;
– fill the shrink cracks in very large concrete structures such as dams;
– fill the space between the concrete foundations and process vessels, tanks and exchangers in industrial plants.
– And, finally, grout is used to fill the space between the concrete foundation and the equipment base or mounting flange of ROTATING MACHINERY