Waterproof Grouting Solutions for Concrete Expansion and Settlement Joints

https://www.dunqianqiu.com/waterproof-grouting-solutions.html

Concrete expansion joints and settlement joints are designed to accommodate structural movement, but they can also become potential paths for water penetration. When joints open, shift, or develop leaks, sealing only the visible surface may not provide sufficient protection. The grouting material needs to penetrate the joints and surrounding cracks, form an effective water-stop barrier, and accommodate structural movement.

For these conditions, XT-301 Acrylate Grouting Material provides a water-soluble grouting solution for sealing concrete cracks, expansion joints, and settlement joints. It uses a three-component system and is injected through a twin-line grouting pump to form an elastic gel within the leakage paths.

Seal Water-Leaking Expansion and Settlement Joints

Expansion and settlement joints can develop leaks when water finds a path through the joints or connected cracks. Surface sealing alone may leave internal water channels untreated.

XT-301 is injected directly into the leakage area. During twin-line grouting, Solution A and Solution B are injected at a 1:1 volume ratio. The two solutions mix at the nozzle and enter the cracks, where they form a water-stop gel to seal the seepage paths.

The treatment process can be summarized as follows:

Joint leakage → locate the leakage path → inject XT-301 → gel forms inside the cracks → seal the seepage path.

Use Low Viscosity to Reach Fine Cracks

The ability of a grouting material to penetrate fine cracks is important when leakage extends beyond a large, visible joint.

XT-301 has an extremely low viscosity of less than 10 mPa·s, with a tested viscosity of 8.7 mPa·s. This high injectability allows the material to penetrate fine cracks and leakage paths. During application, the recommended grouting pressure is 0.2–0.6 MPa, adjustable according to crack-sealing results and structural conditions.

Rather than simply covering the visible joint, low-viscosity grout helps reach internal leakage paths and form a sealing barrier where it is needed.

Accommodate Structural Expansion and Contraction

Movement is a major consideration when treating expansion and settlement joints. The sealing material needs to maintain its function as the concrete structure expands or contracts.

After curing, XT-301 forms an elastic gel with an elongation of more than 600%. The product's tested elongation at break exceeds 800%. This elasticity helps the cured gel accommodate structural expansion and contraction.

The sealing process can be summarized as follows:

Structural movement → joint width changes → elastic gel accommodates deformation → continued sealing of the treated area.

Maintain Water-Sealing Performance in Wet Conditions

Water is often present at leakage locations before grouting begins. A suitable injection material therefore needs to perform under wet conditions.

XT-301 can still form an effective water-stop gel when diluted with water at a 50% ratio. The cured gel also has a permeability coefficient of no greater than 1 × 10⁻⁶ cm/s, while the product's reported test result is 0.

These properties support its use in applications where the primary objective is to control water penetration through concrete cracks and joints.

Provide Strong Adhesion to Concrete

The sealing material also needs to maintain contact with the concrete substrate after injection and curing.

XT-301 provides good bonding with concrete, with bond strength exceeding the strength of the gel itself. The technical test results indicate cohesive failure within the gel rather than failure at the concrete bonding interface.

This helps create an integrated sealing effect between the cured gel and the surrounding concrete instead of relying solely on a surface-applied seal.

Adjust Gel Time for Different Grouting Conditions

Different leakage conditions may require different working and curing times. XT-301 uses Component C to adjust the gel time.

Depending on the amount of Component C added, the listed gel times at 25°C range from approximately 15–20 seconds to 170–190 seconds. A retarder can also be used when a longer gel time is required.

This adjustable gel time provides greater control over the injection process:

• Faster gel time: Suitable for applications requiring rapid leak sealing.

• Slower gel time: Allows more time for grout movement and penetration before gel formation.

The actual gel-time setting should be selected according to the leakage conditions and the manufacturer's application guidance.

http://www.dunqianqiu.com
Guangdong Shenfeng Building Materials Technology Co., Ltd.