Product Data Sheet Show all documents

SikaRapid®-8 Slag

Hardening accelerator

SikaRapid®-8 Slag is a chloride-free hardening accelerator specially developed to promote the early age strength of concrete manufactured using slag without negatively influencing final strengths.

SikaRapid®-8 Slag provides the following advantages through accelerated hardening of the concrete:
  • Faster turnaround of formwork in precast applications
  • Reduced or eliminated steam curing
  • Fast construction processes and early load bearing capacity
  • No negative effects on final strengths
When used with a superplasticizer, SikaRapid®-8 Slag will not change the fresh concrete properties produced by the superplasticizer.
Product Data Sheet Show all documents

Usage

SikaRapid®-8 Slag is especially suitable for any application where fast early strength development plays a major role or is of crucial importance. SikaRapid®-8 Slag is used for the following applications:
  • Precast concrete
  • Ready-mixed concrete where early demoulding is essential
  • Ready-mixed concrete where minimum time delays are critical.
 

Advantages

SikaRapid®-8 Slag provides the following advantages through accelerated hardening of the concrete:
  • Faster turnaround of formwork in precast applications
  • Reduced or eliminated steam curing
  • Fast construction processes and early load bearing capacity
  • No negative effects on final strengths
When used with a superplasticizer, SikaRapid®-8 Slag will not change the fresh concrete properties produced by the superplasticizer.

Packaging

Bulk

Colour

Reddish liquid

Product Details

Product Information

Shelf Life

Thirty-six (36) months from date of production when stored as stated.

Storage Conditions

Store at temperatures between +5°C and +30°C. Protect from direct sunlight and frost.

Density

1.13 ± 0.03

pH-Value

~9

Total Chloride Ion Content

≤ 0.1 %
Technical Information

Concreting Guidance

REMINDER: Concreting in cold weather

The role of an accelerator is only to activate the cement hydration process.

This process is only possible if the initial temperature of the concrete is greater  than or equal to + 5°C.  In this case, the accelerator activates the exothermic setting reactions and generates an internal temperature sufficient to ensure the hardening of the concrete, even if the outside  temperature drops below 0°C.

Application

Application Information

Dispensing

SikaRapid®-8 Slag is added to the gauging water, or added with it, into the concrete mixer.

SikaRapid®-8 Slag may also be added into the ready-mix truck on site. When added on site the truck mixer shall rotate its drum at maximum revolutions for at least 1 minute per m³ of concrete and a minimum of 5 minutes to achieve a uniform mix. The concrete should be visually checked for uniform consistency before discharging.    

Compatibility

SikaRapid®-8 Slag is compatible with Sika® ViscoCrete and Sika Plastotcrete®/Plastiment® admixtures.


When used with a plasticizer or a superplasticizer, an increase in the fluidity of the concrete can be observed.  It is then necessary to reduce the dosage of the plasticizer / superplasticizer and / or reduce the dosage of water. In all cases, a preliminary test is recommended.
Consumption

Recommended Dosage

0.5%  to 5% of the weight of binder or cement depending on the performance sought.

Documents