Below is a list of shotcrete specifications that we get the most requests for from inspectors, General Contractors, and Engineers. For a complete set of ACI 506 shotcrete specifications visit www.concrete.org. The following ACI Shotcrete sections may be out of date. Please visits the ACI website for the most current Shotcrete specifications.
The specifications written in the ACI 506 manual for shotcrete are guidelines for the proper installation of quality concrete and in most cases should always be followed. Although there are always special circumstances that all shotcrete installers run into from time to time that the 506 doesn’t apply. It is in those situations that we have to use our best judgement and experience to create that successful placement.
Shotcrete is a method of applying concrete projected at high velocity primarily on to a vertical or overhead surface. The impact created by the application consolidates the concrete. Although the hardened properties of shotcrete are similar to those of conventional cast-in-place concrete, the nature of the placement process results in an excellent bond with most substrates, and rapid or instant capabilities, particularly on complex forms or shapes. The shotcrete process requires less formwork and can be more economical than conventionally placed concrete. Shotcrete is applied using a wet- or dry-mix process. The wet-mix shotcrete process mixes all ingredients, including water, before introduction into the delivery hose. The dry-mix shotcrete process adds water to the mix at the nozzle. Ref. ACI www.concrete.org