>9 Questions Before Making Shotcrete Mix Design

Posted: February 17, 2011 in Uncategorized


Before making a mix design for shotcrete or sprayed concrete, it is needed to get sufficient information from the clients.
Adequate support information will be resulted in technically and economically effect for the work. A proper mix design assure a successful trial and thus, successful application on site.

Hereafter is a list of 9 questions to the ask the clients prior to making a shocrete mix design:

1. The location of shotcrete to be applied? Slope stabilization, overhead and wall in tunnel
2. Wet or Dry process will be applied? Normally, dry process for slope stabilization, wet process for tunnel lining.
3. The requirement of early strength (8 hours, 72 hours, 7 days, 28 days) and the final strength at each location.
4. Slump requirement (for wet process only)
5. What accelerator admixture to be used? Please note that it would be better to use liquid admixture in rainy season.
6. What is the concrete spraying machine to be used? Rotor Machine (for both wet and dry process) or Pump Machine (wet process only)
7. What kind and type of cement to be used (cement should be super fine. Blain Surface fineness is greater than 4000 square centimeter per gram) PC cement is most suitable for early strength requirement.
8. A dispenser system need to be installed in case wet process is used. Is such liquid dosing unit available?
9. Any other information is helpful in designing shotcrete mix?

Once these question get answered, the mix designing process can be started. For shotcrete or sprayed concrete, trial is a must be prior to the issue of mix design for actual application.

Related Civil Engineering Articles

  • Shotcrete mix design and proportion
    Aggregate Aggregates for shotcrete my contain river sand, crushed sand and crushed stone with particle sizes up to 16mm, normally up to 9.5mm. Here after is a typical and recommended gradation of com…
  • Shotcrete Components
    Shotcrete has been widely used for tunneling works and slope protection, it is also used for architectural purposes. There are two types of shotcrete application, the wet and dry process. Shotcrete i…
  • Fibre Reinforced Concrete
    Conventional concrete containing discontinuous discrete fibres is called fibre-reinforced concrete. Fibers of various shape and size produced from steel, plastic,  glass, carbon and natural materials…
  • Underground Construction Terms
    Underground Constructions Due to the different functions the underground construction have to be divided in the following constructions: The tunnels are mainly underground constructions for transpor…
  • Specification for Shotcrete in Tunnel Construction
    This Specification describes the requirements for shotcrete lining in a tunnel project. Applied shortly after excavation, the shotcrete lining shall rapidly medigate any disintegration or detrimental…



Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s