Abstract
It is known that rebound of shotcrete varies according to internal pressure of a hose and spray distance. Internal pressure of a hose is determined by air flow that conveys concrete. Thus I evaluated relationship of rebound and air flow of a hose. As for spray distance, forms of rebound vary according to it, so I evaluated rebound classifying them according to its form splashes and drops. These results lead to a fact that shotcrete velocity and diffusion area influence on causes of rebound. Therefore I calculated energy of concrete projected by a nozzle by measuring its velocity. As a result, it shows that rebound can be controlled by setting up air flow and spray distance properly.
