LIGHTWEIGHT CEMENT COMPOSITION FOR EXTRUSION MOLDING

摘要

PURPOSE:To obtain a nonasbestine lightweight cement composition used for expansion molded hollow panels for civil engineering and construction. CONSTITUTION:The lightweight cement composition for extrusion molding comprises powder of cement and a siliceous material which are matrix constituent components and pulp in an amount of 1-3 pts.wt. based on 100 pts.wt. powder of the cement and siliceous material. This cement composition contains 2-200 pts.wt. volcanic eruptions such as silas, clay or volcanic ash and/or 2-50 pts.wt. lightweight aggregate prepared by thermally expanding the volcanic eruptions as a raw material as the siliceous material. The lightweight aggregate has <=100mum average particle diameter and >=0.9 apparent density. This composition withstands a high extrusion molding pressure, has a high molding speed and is capable of performing sufficient extrusion molding with sufficient shape retaining properties for a hollow material having >=30% percentage of hollowness. The hardened product has a high strength and is excellent in fire resistance and durability.