What is the purpose of a field grout slump test when preparing to grout masonry cores?

• A. To verify grout color.
• B. To measure grout density.
• C. To test compression strength of grout.
• D. To verify grout consistency and flow to ensure proper fill without segregation.

Answer: (D)

The key idea is that a field grout slump test checks how workable the fresh grout is on site. It measures consistency and flow—how thick or fluid the grout is and how well it will move to fill all the voids in masonry cores and around any reinforcement. This matters because grout that is too stiff won’t penetrate into narrow spaces, leaving voids, while grout that’s too runny can segregate, with fine material separating from aggregates and washing out or settling. The slump test gives a quick on-site indication that the grout will fill evenly and stay homogeneous as it’s placed.

Grout strength, color, or density are assessed later through other tests on cured samples, not by the slump test.