1907: In the USA, Carl Akeley invented the dry spray machine
1910: Double chambered cement gun introduced to construction industry
1920s: Gunite mortar used to fireproof mine drifts
1930s: American Railway Engineering Association introduced the term ‘shotcrete’ to describe the gunite process
1940s: Coarse aggregates introduced
1950s: Shotcrete first reported use in Australian slope stabilisation and refractory linings
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