ABSTRACT
This chapter provides a comprehensive review of important performance requirements for both plastic (fresh) and hardened shotcrete. Rheological properties of plastic shotcrete required to provide suitable pumpability and shootability are discussed. Important parameters include workability (as measured in a slump test), air content as-batched and as-shot, setting time, adhesion, cohesion and resistance to sagging and sloughing. With respect to hardened shotcrete, mixtures are required to be proportioned to meet specified strength and durability requirements. Important parameters include the water/cementing materials ratio and absorption and volume of permeable voids. In fibre-reinforced shotcretes, various toughness requirements are typically specified. In structures exposed to chlorides, limits set for various chloride penetration tests are required to be met. For shotcrete exposed to cycles of freezing and thawing and/or deicing chemicals, requirements for the parameters of the air-void system in the hardened shotcrete must be met in order to provide the shotcrete with durable performance in these aggressive exposure environments. There is also discussion on tests required to measure the Transport Properties of shotcrete for input into Service Life Prediction Models.
