1. Using Superplasticizer in Masonry Grout
By Evan Cope, E.I.T.
Concrete Materials Engineer
Geneva Rock Products

2. Why Use Superplasticizer in Masonry Grout?
High lift grouting is a common practice in today’s masonry industry. It allows masonry walls to be built more efficiently, and at a lower cost. High lift grouting requires a grout with higher slump so the grout can easily flow and consolidate in the lower portions of the masonry walls. Many engineers are specifying grout slumps of 8 to 11 inches. To maintain grout quality at higher slumps, superplasticizer must be used.

3. Why can’t I just add more water to increase my slump?

4. Water to Cement Ratio

6. Segregation

7. Grout Mix Design – H.R.W.R. vs No H.R.W.R.
Constituents
Grout w/o H.R.W.R.
Grout w/ H.R.W.R.
Cement
555 lbs
Flyash
125 lbs
Pea Gravel
841 lbs
Sand
1963 lbs
Water
39 gal or 325 lbs
Low Range Water Reducer
20 lq oz
13.5 lq oz
High Range Water Reducer
None
78 lq oz

8. How Does this Affect Slump?
Mix without H.R.W.R.
Mix with H.R.W.R.

9. How H.R.W.R. Works