RLA Penaflow Panel Grout

For structural support underneath precast concrete panels, filling core holes, and underpinning concrete sections, RLA Penaflow Panel Grout provides a shrink-compensated, Class A cementitious barrier that eliminates settlement gaps. It is formulated to expand in its plastic state to ensure complete void filling, maintaining load-bearing contact across cavities and base infills without staining adjacent substrates.

Plastic state expansion

Penaflow Panel Grout utilizes a gaseous expansion mechanism that operates while the grout is still in a plastic state. This controlled 1% to 2% expansion begins 15 minutes after mixing and finishes within 3 hours, pre-empting the natural shrinkage and settlement common to standard cementitious mixes. The non-metallic formulation contains no iron, preventing rust staining on exposed concrete faces or panel joints. The grout can be placed at thicknesses from 20mm up to 150mm in a single application, allowing installers to pack, pour, or pump the material depending on the access limits of the joint.

Numbers that matter

• 55 MPa compressive strength: Reaches high strength at 28 days (tested to AS1012.9 and AS2073) to sustain heavy structural loads under precast panels and concrete sections.
• 20mm to 150mm application depth: Enables deep single-pass placement in cavities, gaps, and core holes without requiring layered lifts.
• 1% to 2% plastic expansion: Volumetric expansion occurs between 15 minutes and 3 hours after mixing to counteract plastic shrinkage.
• >10 MPa slant shear bond strength: Achieves strong adhesion to concrete substrates at 28 days (tested via ASTM C882-1987) to resist shifting under load.
• 0% bleeding: Zero-bleed formula prevents water separation, maintaining a homogeneous mix that will not weaken the upper bond line.

Where to use it

• Grouting underneath precast panels and structural concrete sections.
• Filling core holes created in panels by core drilling.
• Filling cavities, gaps, and base infills.
• Core filling in concrete block work.
• Underpinning existing concrete structures.
• Securing and filling around anchor bolts.

Limitations

• Do not mix by hand: Must be mixed mechanically with a forced-action mixer, high-shear mixer, or electric drill with a spiral paddle at 500-600 rpm.
• Water ratio limits: Do not add water beyond the specified limits (maximum 4.0L per 20kg bag). Excess water causes segregation, bleeding, and reduced strength.
• No dry application: Never apply mixed grout to a dry, porous substrate. Saturated surface preparation is required.
• Do not vibrate: Do not use mechanical vibrators to assist the flow of the grout; use a header box to maintain gravity flow.
• Unrestrained areas: Keep unrestrained grout areas to a minimum to ensure structural performance.
• Temperature boundaries: Apply only between 10°C and 30°C. Low temperatures delay setting and strength development; high temperatures accelerate setting and increase cracking risks.

Preparation and installation

All concrete substrates must be clean, sound, and free from curing compounds, dust, oil, or grease. Prepared areas must be saturated with water for 4 hours before grouting to reduce substrate porosity. All standing water and puddles must be removed from holes and cavities before placement begins.

When grouting under base plates, bleed holes or venting holes must be provided to prevent pressure build-up. Formwork must be watertight, which can be achieved by sealing the joints with foam rubber strips, polyurethane, or silicone. Construct the formwork to maintain a continuous grout head above the level of the underside of the base plate, allowing gravity flow without trapping air.

Mix the grout by adding the powder to pre-measured cold water. Mix for 3 to 5 minutes until homogeneous. Discard any mix that has stiffened or become unworkable.

Consistency and yield

• Dry Pack / Stiff Grout: 2.7 to 2.9 litres of water per 20kg bag. Yields approximately 10.3 litres per bag. Initial set at 1.5 hours; final set at 2.5 hours.
• Plastic / Trowellable Grout: 3.0 to 3.4 litres of water per 20kg bag. Yields approximately 10.6 litres per bag. Initial set at 3 hours; final set at 4.5 hours.
• Flowable / Pourable Grout: 3.6 to 4.0 litres of water per 20kg bag. Yields approximately 11.0 litres per bag. Initial set at 4.5 hours; final set at 6.5 hours.

Curing

Curing is critical to the final strength and performance of the grout. Upon completion of placement, cure all exposed grout surfaces immediately using plastic sheeting, wet hessian, or a wet liquid curing compound from the RLA Curecon range.