Shotcrete

Shotcrete is concrete or mortar pneumatically projected at high velocity through a hose onto a surface or formwork, compacting itself on impact without the need for conventional formwork and vibration, distinct from ordinary poured concrete in both application method and the equipment required. Developed in the early twentieth century, initially for museum diorama work before its structural potential was recognized, it is used architecturally for curved and irregular structural shells, swimming pools, retaining walls and tunnel linings, and its ability to build up thickness in successive passes on vertical or overhead surfaces makes it well suited to complex sculptural and thin-shell concrete forms that conventional formwork would struggle to achieve.