Cemgrout HS


Cemix® Cemgrout HS is a high strength, high flow, non-shrink cementitious grout. It contains admixtures that provide positive expansion when the grout is in its plastic state and is also shrinkage compensated when in the hardened state. Characteristics include high flow, plastic expansion, high early & ultimate strengths, shrinkage compensation, excellent substrate adhesion and durability.

Typical Application / Uses:

Cemix® Cemgrout HS may be used for:

  • All high performance high strength grouting applications
  • Structural bearing pads
  • Machine and equipment support
  • Tank support
  • Structural base plate support
  • Anchors, bolts, starters & dowels
  • Void filling
  • Tunnel lining grouting
  • Precast connections and between precast elements
  • Wind turbine support


  • Very high strength
  • High flow
  • Pourable or pumpable
  • One component
  • Shrinkage compensated
  • Short curing times
  • High bond strength
  • Durable
  • Low chloride ion permeability
  • Improved abrasion resistance


Substrate Preparation:

Substrates should be clean & free from all contaminants, loose particles, coatings, curing compounds, dirt, mould, oil etc. Substrates must be sound, rough & dampened to ensure a good bond.

Formwork Preparation:

The area to be grouted must be enclosed with good quality rigid watertight formwork. The formwork should be constructed with enough room to use a grout header box system. The formwork must be able to rigidly confine the Cemix® Cemgrout HS until it has set. Treat the formwork with a Cemix® form release agent. Formwork should be flushed out just prior to application.

Header Box & Air Vents:

Use a suitable grout header box delivery system to pour the product into place. Create a head of pressure in the header box to force the grout into place. Keep the header box full of grout at a level well above the finished grout level. Avoid air entrapment by applying from one side and use suitable air vents to vent air as the grout flows into place.

Movement / Control Joints:

Honour any control joints in the concrete substrate – do not apply product over control joints. Create control joints in the grout as required especially in long thin sections.


Mix whole bags of product. Mix thoroughly for 4 to 5 minutes using a drill & paddle or suitable mechanical grout mixer. If a less fluid consistency is required, less water can be added. More water will increase flow but reduce strengths. Add 3.0L of water to the mixer & then add the product to the water. Add rest of water slowly whilst mixing until the desired consistency is achieved. Typical total water for a fluid consistency is approximately 3.3L per 20kg bag. In very hot weather use chilled mixing water. In very cold weather use warmer mixing water. Re-mix product every 10 minutes or if it has been sitting for a while.


Saturate the concrete substrate with water just prior to grout application. Avoid water ponding. Typical application depths are from 10mm to 200mm. Pour the Cemix® Cemgrout HS into place while the substrate is still damp. Use a suitable header box delivery system and air vents as described above. Application is from one side only completely filling the void & avoiding air entrapment. Rod grout to move & compact as required. Trowel finish as required.


It is very important to prevent early plastic state moisture loss prior to the product setting. Cure product thoroughly after it has set by keeping it wet and covered for at least 7 days or until the desired strength has been reached.

Technical Data:

Appearance – Sand/Cement grey powder

Strength (MPa) – 50MPa @ 2 days; 90MPa @ 28 days; Restrained; 3.3L of water

Application Temp – 5˚C - 30˚C.

Yield / Coverage – Approximately 10.5L or 0.0105m3 per 20kg bag at 3.3L of water.

Bond Strength – >3MPa.

Height Change – Positive expansion.

Thermal Coeff. Of Exp – 9.0 x 10-6 mm/mm/˚C

Chloride Ion Permeability – <1000 coulombs

Working Time – 45 minutes at 20˚C.

The data shown above reflects typical results based on laboratory testing under controlled conditions. Reasonable variations may occur on site.

Mixing Water Dosages:

3.3L – 0.0105m3 – semi-fluid – 2days 50MPa 28days 90.0MPa


Do not apply product to surfaces less than 5OC and more than 30OC.


  • Large/deep volumes of grout can generate excessive heat whilst hardening. This may lead to thermal cracking. For large volume applications consider using Cemix® Structural Repair Flowable.
  • In very hot weather, use chilled mixing water.
  • In very cold weather, use warm mixing water.
  • More mixing water will increase flow but reduce strengths.


Clean all tools with water & brush immediately after use.

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