| 摘要 |
PROBLEM TO BE SOLVED: To provide a powdery quick setting agent which can stably be added to spraying cement concrete, and more specifically, has capabilities such as those of stably being discharged from a feeder or product silo of the agent, reducing occurrence of any segregation in it or any dust formation in it when handled and also reducing the volume of its packaging bag, and further, is capable of preventing peeling-off of a sprayed surface with the spraying cement concrete, increase in rebound of the spraying cement concrete, increase of dust, etc., from being caused and producing a homogeneous spraying cement concrete hardened body, and also to provide a cement composition using the powdery quick setting agent as a component. SOLUTION: This powdery quick setting agent contains an agglomerated powder formed by agglomerating primary particles of at least one of constituent powdery raw materials of the agent and the constituent powdery raw materials are powdery calcium aluminate, a powdery sulfate and/or a powdery alkali metal aluminate, and further optionally, in addition to these powdery compounds, a powdery alkaline earth metal hydroxide and/or a powdery alkali metal carbonate. This cement composition contains cement and the powdery quick setting agent. |
