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What is shotcrete and when is it used?

Q. What is shotcrete and when is it used?


A. 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. Shotcrete is used in new construction and repairs and is suitable for curved and thin elements (ACI 506R).


References: SP-1(02); ACI PRC-506-22; ACI 506.2-13; ACI 506.4R-19; ACI PRC-506.1-21; CCS-4(20); ACI PRC-506.5-22; American Shotcrete Association

Topics in Concrete: Concrete Fundamentals; Shotcrete; Repair of Concrete

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