CONCRETE COMPOSITION USED FOR SHIELD DRIVING DIRECT PLACING METHOD AND ITS PRODUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a concrete composition used for a direct placing concrete lining material in a shield driving method and having excellent early strength developability and excellent water resistance.;SOLUTION: In the case of producing the concrete composition used for the shield driving direct placing method, an additive containing a 1st water-soluble low molecular compound (A) and a 2nd water-soluble low molecular compound (B) in addition to a chemical admixture for concrete and selected from additives each in a combination that the compound (A) and the compound (B) are respectively a compound (A) selected from ampholytic surfactants and a compound (B) selected from anionic surfactants, respectively a compound (A) selected from cationic surfactants and a compound (B) selected from anionic surfactants or respectively a compound (A) selected from cationic surfactants and a compound (B) selected from bromine compounds is blended as a thickening admixture .;COPYRIGHT: (C)2006,JPO&NCIPI