What is the difference between dry and wet process shotcrete?
A. In the dry processes the dry mix of cement, aggregates, additives and possibly fibers are blended and delivered by the hose to the nozzle by compressed air. The mixing water is added at the nozzle, mixed with the dry material while being delivered to the area of placement. In the wet process the mortar or concrete is premixed with water in a mixer and pumped through a hose to the nozzle. The compressed air brought to the nozzle delivers the mix to the area of the placement. Both processes have their advantages and disadvantages and both are used in concrete restoration. For more detailed information please see a presentation titled Shotcrete in Concrete Restoration.
