Product Data Sheet Show all documents

Sikament® RB 857 T

(former MRheobuild 857T)

High range water-reducing and slump retaining concrete admixture

Sikament® RB 857 T is a highly effective dual action liquid superplasticiser that imparts excellent slump retention for prolonged periods.
Suitable for use in hot and tropical climatic conditions.

Sikament® RB 857 T provides the following properties:
As a Superplasticiser:
  • Workability is greatly improved
  • Concrete is placed easily
  • Especially suitable for slender components with densely packed reinforcement
  • Concrete requires less vibrating
  • Improved cohesion of the concrete mix significantly reduces the risk of segregation and allows greater time for placement

As a Water Reducer:
  • Impressive water reduction capability
  • Final strength improvement
Product Data Sheet Show all documents

Usage

Sikament® RB 857 T can be used as a superplasticizer for the production of free flowing concrete for:
  • Slabs
  • Foundations
  • Walls
  • Columns
  • Piers
  • Piles
  • Slender components with dense reinforcement
 

Advantages

Sikament® RB 857 T provides the following properties:
As a Superplasticiser:
  • Workability is greatly improved
  • Concrete is placed easily
  • Especially suitable for slender components with densely packed reinforcement
  • Concrete requires less vibrating
  • Improved cohesion of the concrete mix significantly reduces the risk of segregation and allows greater time for placement

As a Water Reducer:
  • Impressive water reduction capability
  • Final strength improvement

Packaging

1000 L flowbin or bulk supply in tanker

Colour

Dark brown liquid

Product Details

Sustainability / Certifications / Approvals

CERTIFICATES AND TEST REPORTS

Sikament® RB 857 T follows the requirements of ASTM C494; Type G and EN 934-2
Product Information

Composition

Sulphonated napthalene

Shelf life

12 months from date of production if stored properly

Storage conditions

Store in undamaged, unopened, original sealed packaging in dry conditions at temperatures between +5°C and +50°C. Mix well before using.

Density

~1.22 kg/l (+25°C)

Total chloride ion content

Nil

(EN 934-2)
Technical Information

Concreting guidance

The standard rules of good concreting practice for production and placing must be observed when using Sikament® RB 857 T in concrete. Refer to relevant standards.
Fresh concrete must be cured properly especially at high temperatures in order to prevent plastic and drying shrinkage. Use Sika® Antisol® products as a curing agent or apply wet hessian.

 

Application

Application Information

Dispensing

Sikament® RB 857 T is a ready-to-use admixture to be added to the concrete as a separate component. Optimal result is obtained if Sikament® RB 857 T is poured into the concrete mix right after the addition of the first 80% of the mixing water, i.e. when all solids are wetted. Avoid adding the admixture to the dry aggregates.

Compatibility

Sikament® RB 857 T is suitable for mixes containing all types of cement and supplementary cementitious materials such as: Microsilica (Silica Fume), Fly Ash (PFA), GGBS (Ground Granulated Blast Furnace Slag) and the following Sika® products:
SikaPump®, Sika®FerroGard®, SikaFume®, SikaFiber®, Sika® Aer, Sika® Stabilizer, SikaControl®.
We recommend to perform trial mixes to establish the required performance when combining Sikament® RB 857 T with the above products or other admixtures. Please consult our Sika Technical Department.
Consumption

Recommended dosage

0.8 - 2.0 % by weight of binder
Other dosages by weight of binder can be used depending on the mix design, raw materials, climatic conditions and concrete requirements.
Trial mixes must be performed to establish the exact dosage rate required.

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