Alkali-free, liquid high-performance set accelerator for shotcrete

Product Description

TYTRO® SA 528 is a high-performance, alkali-free set accelerator specifically formulated to provide high early strength at low dosage rates and improve productivity by shortening the time of setting without compromising long-term strength and durability.

TYTRO® SA 528 is an easy flow, ready-to-use non–alkaline and environmentally neutral liquid suspension, and is formulated to comply with the requirements of ASTM C 1141/C 1141M, Types I /II, Grade 9, Class A.

Product Advantages

  • Efficient dosage rate
  • Reduced excavation downtime – Increased adhesion and faster setting
  • Improved strength – Increased early age strength development without compromising later age strength
  • Reduced cycle times – Quicker setting action and increased layer thickness for overhead work
  • Minimum material waste – Lower rebound and dust
  • Safer and healthier to handle – Non-alkaline formulation
  • Robust and easy to formulate – Liquid product; easily measured and dosed
  • Versatile – Wet as well as dry-mixed process


TYTRO® SA 528 is used in all shotcrete applications where high early strength is required, especially in the following applications:

  • Temporary and permanent rock support in tunnels
  • Underground rock support in mining
  • Slope stabilization

Addition Rates

The dosage of TYTRO® SA 528 can vary based on the type of application, mix design, cement type and content, water-to cementitious materials ratio, temperature of the concrete, ambient temperature and temperature of the substrate on which the concrete is to be applied.

The dosage of TYTRO® SA 528 normally ranges between 3% and 8% by the total weight of cementitious materials. Overdosing (> 10%) may result in decreased final strength. Should conditions require using more than the recommended addition rates, please consult your GCP representative.

GCP recommends that trials be performed before use to assess and optimize dosage rates and shotcrete performance.


TYTRO® SA 528 is added at the nozzle. TYTRO® SA 528 is a suspension and therefore not all types of dosing pumps will work properly. Advice on dosing pumps is available from GCP on request.


TYTRO® SA 528 is available in drums and totes. In North America, TYTRO® SA 528 is also available in bulk, delivered by metered tank trucks.



TYTRO® SA 528 should be stored at a temperature range of 5°C to 35 °C. It is recommended that your local GCP sales representative be consulted prior to the use of any products that may be frozen. Performance tests should always be carried out prior to use.


TYTRO® SA 528 must be kept in closed plastic containers or closed tanks made of polypropylene, polyethylene, or PVC. Do not store in steel containers as the pH can cause corrosion which might affect the performance of the product. Containers must be tightly closed every day to avoid contact with air which can cause a chemical reaction (skin building on top and lumps which cause problems with dosing pumps).

After prolonged storage, TYTRO® SA 528 should be vigorously recirculated in the tanks by means of stirring apparatus or through recirculation before use. It can have a settlement that may not be visually detectable.

Shelf life

Shelf life is 3 months. Depending on storage conditions, the shelf life may be greater than stated. Please contact your local GCP sales representative regarding the suitability for use if the shelf life of TYTRO® SA 528 has been exceeded.

Health and Safety

Avoid eye and skin contact and wear rubber gloves and goggles. If contact occurs, rinse with plenty of water. In case of eye contact, seek medical advice. For further information, refer to the SDS (Safety Data Sheet) or contact your local GCP representative.


TYTRO® SA 528 is compatible with all GCP TYTRO® shotcrete admixtures.

GCP recommends that a suitable superplasticizer and slump life controlling admixture be incorporated into the shotcrete mix to achieve extended working life and maintain low water-tocementitious materials ratio. TYTRO® WR high-range water-reducing and TYTRO® HC hydration control admixtures are recommended for this purpose.

Pretesting of the shotcrete mix should be performed before use and as conditions and materials change in order to ensure compatibility with other admixtures.

For use with other shotcrete admixtures systems, we recommend you contact GCP for further advice.


Form Liquid
Color Yellow
Density (g/cm3) 1.40 ± 0.02
pH (25 °C / 77 °F) 3 ± 1
Chloride Content <0.1%
Thermal Stability 5 °C to 35 °C

ca.gcpat.com | North America customer service: 1-877-4AD-MIX (1-877-423-6491)

We hope the information here will be helpful. It is based on data and knowledge considered to be true and accurate, and is offered for consideration, investigation and verification by the user, but we do not warrant the results to be obtained. Please read all statements, recommendations, and suggestions in conjunction with our conditions of sale, which apply to all goods supplied by us. No statement, recommendation, or suggestion is intended for any use that would infringe any patent, copyright, or other third party right.

TYTRO is a trademark, which may be registered in the United States and/or other countries, of GCP Applied Technologies Inc. This trademark list has been compiled using available published information as of the publication date and may not accurately reflect current trademark ownership or status.

© Copyright 2018 GCP Applied Technologies Inc. All rights reserved.

GCP Applied Technologies Inc., 2325 Lakeview Parkway, Suite 450, Alpharetta, GA 30009, USA
GCP Canada, Inc., 294 Clements Road, West, Ajax, Ontario, Canada L1S 3C6.
This document is only current as of the last updated date stated below and is valid only for use in the Canada. It is important that you always refer to the currently available information at the URL below to provide the most current product information at the time of use. Additional literature such as Contractor Manuals, Technical Bulletins, Detail Drawings and detailing recommendations and other relevant documents are also available on www.gcpat.com. Information found on other websites must not be relied upon, as they may not be up-to-date or applicable to the conditions in your location and we do not accept any responsibility for their content. If there are any conflicts or if you need more information, please contact GCP Customer Service.

Last Updated: 2023-06-29