GroutAid® is the essential microsilica additive for improving cement injection grouts


GroutAid® is a microsilica (silica fume) based additive for use in combination with microcement and other cement-based grouts.  The use of GroutAid®  will increase efficiency of injection grouting by improving both the plastic and hardened properties of the grout, enabling injection into soils and cracks in rock and concrete.  This improved permeation capability of cement-based grouts further reduces the need to use chemical grouts with the subsequent advantages of cost reduction and environmental safety.

The advantages of using microsilica in cement-based systems are well known from concrete technology.  The microscopic particle size and pozzolanic reactivity of microsilica act to reduce bleeding and segregation, develop stronger and less permeable concrete, and increase the durability and resistance to chemical attack.  These same properties are also important for injection grouts.

GroutAid® improves the properties of the injection grout and the injected formation:

  • Stability
  • Penetration
  • Strength
  • Permeability
  • Durability
  • Environment
  • Economy 

Applications & Dosage

GroutAid® is suited to all applications where cement-based grouts are used currently.

Dosage can vary from 5% upward, depending on application and the nature of the cements.

Specific advice may be provided by Elkem representative or authorized agent. 

Contact Elkem using the message form on the Elkem GroutAid® web page.


GroutAid® will provide a more cost-effective injection because:

  • Improved penetration implies that cement-based injection can be performed in finer soils and cracks than was possible before, and may reduce the use of expensive chemical grouts.
  • Improved penetration implies that the number of injection holes drilled can be reduced, or alternatively, that the total requirement for injection can be reduced.
  • Material cost can be reduced since the “dry content”is reduced.

Particle Size

The microsilica used in GroutAid® production has been carefully selected and quality-controlled so that the coarse particles content is extremely low, ensuring complete compatibility with the finest of microcements.


A stable, non-segregating grout is extremely beneficial for successful injection. Stable grouts will ensure that cracks and voids will be more thoroughly filled, which can lead to reduced need for injection. The addition of GroutAid means the addition of a great number of extremely fine particles of very high specific surface area. This very high surface area and corresponding internal attraction forces, keep the cement and microsilica particles suspended without settling within the water, even at high water/powder ratios.


GroutAid® is a non-toxic, mineral based product.
Injection grouts based on cement and GroutAid® have a positive impact on the environment through:

  • Reducing the need for potentially harmful chemical grouts.
  • Reducing permeability that will contribute to a decreased risk of leaching of harmful substances through soils –such as in landfills.


25 litres, 200 litres, 1000 litres and bulk in road tanker.

GroutAid® is an aqueous suspension of microsilica.

GroutAid® chemical composition and physical properties are regularly checked, and the following limits have been set:

Chemical composition
SiO2 (Silicon dioxide, amorphous) % minimum 86
C (Carbon) % maximum 2.5
LOI (Loss on ignition) % maximum 3.0

Physical properties
Slurry density kg/m3  1360 - 1420*
Solids content % wt 48.0 - 52.0
Surface area, dry m2/g minimum 15
Viscosity mPas 100
Coarse particles (+45 µm) % maximum 1.0
pH   4.0 - 7.0
Colour   Grey

* When packed

Test methods

Material data given in this datasheet refer to analysis according to Elkem Standard Test Methods for Microsilica (ESTMS).  Test methods available on request.