Greater Durability

The most significant development in improving shotcrete quality has been the introduction of automated shotcrete by DYK. This enhanced shotcrete technology helps assure the durability of DYK's structures into the next century.

DYK has discovered that an automated shotcrete application greatly enhances the protective function of the shotcrete covercoat when compared to hand-applied shotcrete. Hand-applied shotcrete is subject to numerous variables, (such as distance from wall, applied thickness, up-and-down and side-to-side shooting angles, and nozzleman experience) which if not correct, diminish the final quality.

Increased Productivity

The only practical method of controlling these variables is an automated shotcrete process. The task of properly applying shotcrete by hand, over a large surface area, with the number of layers required for the typical prestressed concrete tank, is particularly daunting. The tendency with hand-applied shotcrete is to build up thick layers and move on.

With automated equipment, however, numerous thin layers can efficiently be built up, providing a better, more uniform cure. The automated procedure also increases productivity, protecting the Owner from operational problems or penalties if the tanks are not completed on time.

Structural Quality and Reduced Cost

Wet-mix shotcrete is applied from a nozzle mounted on a mechanized tower which travels around the circular wall or dome-ring at a controlled speed. The nozzle, always held at the proper angle and distance, slowly moves around the tank circumference and up the wall in a uniform spiral path.

To obtain a uniform cure and prevent shrinkage cracking, the shotcrete mix contains polypropylene fibers and the full cover is built up in numerous layers. In addition to improved structural quality, another beneficial side effect of the automated application is reduced cost because of the system's greater efficiency.