Product Data Sheet Show all documents

SikaControl® SRA 872 SA

(former MasterLife® SRA 872SA)

SHRINKAGE REDUCING ADMIXTURE

SikaControl® SRA 872 SA is a shrinkage-reducing admixture, developed specifically to reduce drying shrinkage of concrete and mortar as well as the potential for subsequent cracking.
SikaControl® SRA 872 SA admixture functions by reducing capillary tension of pore water, a primary cause of drying shrinkage. Suitable for use in hot and tropical climate conditions.

SikaControl® SRA 872 SA increases cohesion within the concrete pore system. The contraction caused by water loss is reduced which results in significantly reduced drying shrinkage and therefore shrinkage cracking in correctly designed concrete mixes and structures.
With the application of SikaControl® SRA 872 SA the following advantages can be achieved:
  • Reduced drying shrinkage cracking
  • Reduced potential of slab curling
  • Reduced permeability
  • Increased concrete durability
  • Significantly reduces drying shrinkage by as much as 80% at 28 days, and up to 50% at one year and beyond
SikaControl® SRA 872 SA does not contain chlorides or any other ingredients which promote the corrosion of steel. It is therefore suitable for use in reinforced and prestressed concrete structures.  
Product Data Sheet Show all documents

Usage

SikaControl® SRA 872 SA is used for the production of high performance concrete with greatly reduced drying shrinkage, so that the durability of the concrete structure is significantly improved.
SikaControl® SRA 872 SA is mainly used for the following applications:
  • Structures with strict demands regarding the limitation of crack width
  • In concrete where low drying shrinkage is important
  • In situ concrete floors where reduced shrinkage minimizes risk of cracking for the same joint spacing, which therefore allows wider joint spacing without increasing the risk of shrinkage cracking
  • In thin bonded topping slabs, to minimize the difference in shrinkage from the existing substrate
  • In concrete elements which are restrained against shrinkage
  • Concrete in marine environments for enhanced durability
  • To improve watertightness in water retaining concrete structures by reducing the drying shrinkage of concrete and therefore reducing the risk of crack development
  • Ready-mixed or precast concrete structures requiring shrinkage reduction and long term durability
  • Wet mix shotcrete
  • Mortars and grouts
 

Advantages

SikaControl® SRA 872 SA increases cohesion within the concrete pore system. The contraction caused by water loss is reduced which results in significantly reduced drying shrinkage and therefore shrinkage cracking in correctly designed concrete mixes and structures.
With the application of SikaControl® SRA 872 SA the following advantages can be achieved:
  • Reduced drying shrinkage cracking
  • Reduced potential of slab curling
  • Reduced permeability
  • Increased concrete durability
  • Significantly reduces drying shrinkage by as much as 80% at 28 days, and up to 50% at one year and beyond
SikaControl® SRA 872 SA does not contain chlorides or any other ingredients which promote the corrosion of steel. It is therefore suitable for use in reinforced and prestressed concrete structures.  

Packaging

210 L drum and 1,000 L IBC

Colour

Clear liquid

Product Details

Product Information

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

~1.01 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 SikaControl® SRA 872 SA 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.

Effect on setting

The application of SikaControl® SRA 872 SA will result in retarded setting of the concrete and in cold ambient temperatures this effect will be increased.
When combining SikaControl® SRA 872 SA with retarding admixtures, their combined retardation effect and the delay in setting time has to be taken into account.

Application

Application Information

Dispensing

SikaControl® SRA 872 SA admixture may be added to the concrete mixture during the initial batch sequence or at the jobsite.
The mix water content should be reduced to account for the quantity of SikaControl® SRA 872 SA admixture used.

Compatibility

SikaControl® SRA 872 SA may be combined with all types of Portland cement, concretes containing pozzolanic materials such as: GGBS (Ground Granulated Blast Furnace Slag), Fly Ash (PFA) , Micro Silica (Silica Fume) and the following Sika product ranges / admixtures:
Sika® Plasticisers: Sika® ViscoCrete®, SikaPlast®, Sikament®, Plastiment®
SikaFiber®, Sika® Aer, SikaPump®, Sika® FerroGard®, Sika® Control.
We recommend to perform trial mixes to establish the required performance when combining SikaControl® SRA 872 SA with the above or other admixtures.
Please consult our Sika Technical Department.

 
Consumption

Recommended dosage

1.0 - 4.0% by weight of binder

Dosages outside of this range may be required depending on the level of shrinkage reduction needed.

Knowledge of the shrinkage characteristics of the concrete mixture proposed for use is required prior to the addition of SikaControl® SRA 872 SA admixture. The dosage of SikaControl® SRA 872 SA admixture will be dependent on the desired drying shrinkage and the reduction in drying shrinkage required.
It is strongly recommended that drying shrinkage testing be performed to determine the optimum dosage for each application and each set of materials.

Documents