What is the difference between Gunite and Shotcrete?
The primary difference between gunite and shotcrete comes from the method in which it is applied. Shotcrete is a wet mixture of sand, cement, and aggregate, meaning that the water is mixed prior to arriving at the jobsite. The basic rule of concrete is that its strength is determined by the amount of water the mixture contains. During the gunite process, the water is applied at the end of the nozzle, giving the operator complete control over the amount of water applied and the thickness and texture of the application. With shotcrete, the water is mixed with the sand and cement in the truck, which does not allow the operator to control the amount of water in the shotcrete. In addition, the shotcrete mixture thickens and additional water must be added to keep the mix thin enough to flow through the pump during application, which weakens the final product and results in an inconsistent application.
