When Do You Use Nonshrink Grout?

Uses

• Nonshrink grout is recommended for use under steel columns, sole plates and machinery not subject to constant vibration or heavy impact. Prestressed or post-tensioned cables, anchor bolts and tendons require this nonferrous mixture, as does any concrete repair where rebar is present. This may include tunnels or building foundations, or in setting columns or rails. Nonshrink grout effectively anchors metallic sign posts, parking meters and other metal-based fixtures quickly and permanently in concrete, rock or masonry substrates.

Surface Preparation

• In order to effectively use nonshrink grout, surfaces must be clean and in good structural condition. A brisk brushing with a metal broom or brush is necessary to remove paint, dirt, sand or dust. Surface contaminants containing grease or oil should be removed using a degreasing detergent solution and applying a steady flow of water to clear the area. The surface to be grouted must be saturated with clean water to enhance grout set and adhesion.

Mixing for Consistency

• Add nonshrink grout premix to water until the desired consistency is reached. Applications may vary from dry pack through plastic to flowable or fluid. For dry pack, add the contents of a 55-lb. bag to .86 to .92 U.S. gallons of water. For plastic consistency, increase water to 1.36 US gallons. Flowable requires 1.49 U.S. gallons per 55-lb. bag, and fluid dictates 1.65 gallons. Mix grout at temperatures between 50 and 77 degrees Fahrenheit, and do not exceed 1.7 U.S. gallons of water per each 55-lb. bag.

Placement and Setting

• Nonshrink grout must be placed within one hour of mixing. The substance requires continued mixing, for at least three minutes' duration after each 30 minutes of use, to avoid undesired lumping or settling. Base plate, substrate and grout temperatures require a reading between 41 degrees and 95 degrees Fahrenheit for 72 hours after grouting. Exposed grout must be kept moist for at least three days after placement to ensure proper set.