Product Data Sheet Safety Data Sheet Show all documents

Sika® Sigunit® L-53 TH

Alkali Free Liquid Shotcrete Accelerator For Wet or Dry Shotcrete Process

Sika® Sigunit® L-53 TH is a high performance, liquid, alkali-free shotcrete accelerator.

Sika® Sigunit® L-53 TH provides the following benefits:
  • Alkali free (non-caustic) and classified as non-toxic product
  • Fast to very fast setting of shotcrete mixes according to dosage used
  • No strength loss of the accelerated concrete if used correctly
  • No additional contamination of mountain and ground water due to washed out alkalis
  • Large reduction in rebound as long as the spraying is performed according to the state of the art
  • Improves bond of shotcrete to rock and concrete, making overhead spray easier
  • Free of chlorides, no danger to steel reinforcement and steel fibers
  • Comply with the requirements of the tests as specified in the standard GB/T 35159-2017 Flash setting admixture for shotcrete
Product Data Sheet Safety Data Sheet Show all documents

Usage

Sika® Sigunit® L-53 TH is suitable set accelerator for dry–process as well as for wet process shotcreting. The main fields of applications are:
  • Securing of rock in tunnel and mine construction (preliminary support)
  • Rock and slope stabilization
  • Dewatering work by dry process
  • High quality shotcrete for permanent support by shotcrete
 

Advantages

Sika® Sigunit® L-53 TH provides the following benefits:
  • Alkali free (non-caustic) and classified as non-toxic product
  • Fast to very fast setting of shotcrete mixes according to dosage used
  • No strength loss of the accelerated concrete if used correctly
  • No additional contamination of mountain and ground water due to washed out alkalis
  • Large reduction in rebound as long as the spraying is performed according to the state of the art
  • Improves bond of shotcrete to rock and concrete, making overhead spray easier
  • Free of chlorides, no danger to steel reinforcement and steel fibers
  • Comply with the requirements of the tests as specified in the standard GB/T 35159-2017 Flash setting admixture for shotcrete

Packaging

200 L/drums

Colour

White milky to grey milky liquid.

Product Details

Product Information

Shelf life

3 months from date of production If stored properly in undamaged, original, sealed packaging.

Storage conditions

Temperature storage from +10ºC to 40ºC when stored in dry place and protected from direct sunlight.

Density

1.41 ± 0.05 kg/l (at temperature 25°C)

pH-Value

2.0 - 3.0 Approx.

 

Application

Application Information

DISPENSING

Sika® Sigunit® L-53 TH is added thanks to suitable liquid dosing unit such as Aliva AL 403.4 (24-240 lt/h) or AL 403.5 (30-700 lt/h).

Suitable dosing unit type is determined according to cement content, spraying out-put and the accelerator dosage.

 
Consumption

Recommended dosage

Accelerator dosage depends on many factors and actually should be adjusted as per the site conditions met.
It should not be fixed for one time at all!

The dosage of the accelerator would vary according to the scope of work. Typically if the reduction of the rebound (without early strength) is required the dosage would be 2-4%. If early strength is required, dosage would be 4-6%. It would depend as well as on the type of application,
vertical (benches) spraying or over-head spraying.

The performance of the accelerator would depend on the cement type, content, age and quality, the W/C of the mix, temperature of the mix, the
substrate condition, etc.

As guide line, accelerator dosage – that need to be confirmed by site trial:

Process

Requirement

Dosage

Dry

Rebound reduction or vertical application

~3% by weight of cement

Dry

Early Strength or overhead application

4-6% by weight of cement

Wet

Rebound reduction or vertical application

4-5% by weight of cement

WetEarly Strength or overhead application

5-6% by weight of cement

Concrete temperature should not be lower than 15°C (especially so for thick layers). Lower temperatures require higher dosages.
Application steps

APPLICATION INSTRUCTIONS

The accelerator will be added and mixed with the other concrete components as follows:

Dry Process

Sika® Sigunit® L-53 TH is supplied from the liquid dosing unit to the mixing tube assembly by means of water under pressure (2-3 bars more than the conveying pressure). The mixing tube assembly being located
~ 2.5 meters behind the nozzle or at the nozzle directly.

Wet Process

Sika® Sigunit® L-53 TH is supplied from the liquid dosing unit to the mixing tube assembly by means of air under pressure (2-3 bars more than the conveying pressure). The mixing tube assembly being located
~ 2.5 meters behind the nozzle or at the nozzle directly.

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