CARBON FIBER FOR REINFORCING CEMENT AND PRODUCTION OF CONCRETE USING THE SAME

摘要

PURPOSE: To produce a concrete reinforced with a carbon fiber and having large bending strength by dispersing the carbon fiber having aζ-potential more than a specified value measured by a streaming potential method in a cement matrix. CONSTITUTION: After subjecting the carbon fiber (e.g. carbon fiber derived from polyacrylonitrile) to an electrolytic oxidation treatment usually applied, the fiber is treated with a cationic polymer (e.g. polydimethylaminoethyl acrylate-methylchloride quaternary salt), a cationic surfactant (e.g. lauryltrimethylammonium chloride) or a silane coupling agent (e.g. aminopropyl- triethoxysilane). In this way, the carbon fiber for reinforcing in which the surfaceζ-potential measured by the streaming potential method is >=-10mV in an aq. soln. of pH11-13 same with the cement. Then, this carbon fiber is dispersed in the cement matrix. In this way, adhesion and dispersibility of the carbon fiber are increased, and a high-strength concrete reinforced with the carbon fiber is obtained.