Efficient and Cost-Effective

Dry-mix shotcrete is a highly efficient and cost-effective way to apply concrete or mortar, for both new construction and repair. Properly applied, it's structurally sound and durable. But it requires specialized knowledge, skill and experience. It's not a job for just any contractor. Knowles Industrial Services Corporation has been successfully applying dry-mix shotcrete since 1953. We've developed the in-depth crew training and quality controls necessary to ensure specifications are met or exceeded in accordance with ACI 506.2.

Only an experienced applicator like Knowles employing six ACI certified nozzlemen has the expertise and depth of resources to offer your company the full benefits of dry-mix shotcrete.

Why Consider Shotcrete?

"Shotcrete as a Concrete Repair Option" (9MB)


As a materials supplier, we work closely with many contractors, and Knowles is one of the best shotcrete applicators I’ve ever seen. They follow our procedures for surface preparation and application to the letter, every time. I’ve recommended Knowles to many customers, and they’ve been pleased without fail.
— Dave Jamieson Formerly Northeast Dist Mgr, Sika Concrete Restoration System

Physical Properties of Shotcrete

  • Its high compressive strength, low absorption, low permeability and resistance to weathering or chemicals make dry-mix shotcrete comparable or superior to conventional concrete with the same composition at a much lower water-cement ratio.

Lower Cost

  • Shotcrete eliminates or reduces the need for forms, cranes and pumps, and can be applied at much faster rates than conventional concrete placement or repair methods.
  • The option of thinner reinforced concrete repair overlays not achievable by much more expensive conventional form and pour repairs allow for lower cost, rapid asset gains and quicker return on investment


  • Shotcrete speed of application is dramatically increased where access is difficult, because mixing and application equipment can be set up as far as 1,000 feet from the repair area. Rapid early strength allows for fast turn-around.

Advantages and Versatility

  • Dry-mix shotcrete can be successfully applied on virtually any surface: flat or curved, vertical or sloped, even overhead.
  • Conventional shotcrete, consisting of Portland cement, fine aggregate and potable water, can be enhanced with silica fume or polypropylene fibers to improve cohesiveness, freeze-thaw resistance, and impermeability.
  • Refractory shotcrete contains specially designed cements, such as calcium oxide or aluminas, to resist alkalis and acids, and withstand high temperatures. It is typically used for stacks, boilers, scrubbers, separators and tanks.
  • Special shotcrete includes factory-proportioned latex-modified, potassium silicate, magnesium phosphate, polymer and other proprietary mixtures for added corrosion and chemical resistance.


  • Major concrete activities such as forming, stripping and associated crane work are eliminated reducing risk and improving jobsite safety.

Structural & Non-structural Concrete Repair

  • Bridge Piers & Decks Canals
  • Columns
  • Penstocks
  • Reservoirs
  • Beams
  • Tunnels
  • Pilings & Pier
  • Sewers
  • Retaining Walls
  • Culvert Rehabilitation
  • Tanks
  • Dam Spillways
  • Clarifiers
  • Silos
  • Foundation Walls