grout flow cone test apparatus

What is grout flow cone test apparatus:

The grout flow cone test apparatus is a standard procedure used to measure the fluidity of grout, specifically for specialized applications like preplaced-aggregate concrete or post-tensioning ducts. It essentially measures the “flow ability” by timing how long it takes for a specific volume of grout to pass through a standardized funnel.

Think of it as the “viscosity test” for construction—ensuring the mix is thin enough to fill every nook and cranny, but thick enough to maintain its strength.

What is the Apparatus?

The apparatus is a precision-engineered funnel, typically made of cast aluminum or stainless steel. It consists of:

• The Cone: A funnel with a 7-inch (178 mm) top diameter that tapers down to a specific discharge tube.

• Discharge Tube: A replaceable small-bore tube at the bottom (usually 0.5 inches or 0.75 inches in diameter).

• Receiving Container: A beaker or bucket (usually 1725 mL or 2000 mL capacity) to catch the grout.

How to Work the Apparatus (Step-by-Step)

Testing the flow is grout flow cone test apparatus machine a straightforward process, but it requires speed and precision because grout begins to stiffen the moment it stops being mixed.

1. Preparation

• Leveling: Mount the cone on a steady, level stand.

• Wetting: Dampen the inside of the cone with a moist cloth (but ensure there is no standing water). This prevents the dry metal from “grabbing” the grout and slowing the flow.

• The Finger Plug: Place your finger over the bottom orifice (discharge tube) to seal it.

2. Filling

• Pour the freshly mixed grout into the cone until the surface touches the level indicator (point gauge).

• Ensure the grout is free of large lumps; if necessary, pour it through a sieve first.

3. Timing the Flow

• The Release: Simultaneously remove your finger and start the stopwatch.

• The “Break”: Watch the grout flow into the receiving container.

• Stopping: Stop the watch at the exact moment you first see light through the discharge tube from the top—this is known as the “break in flow.”