APPLICATION OF THE CALCIUMSILICATE - CAS SLAG TYPE CEMENT TO GRC.
作者单位：Chichibu Cement Co.Ltd. TokyoJapan
会议名称：《1985北京国际水泥及混凝土学术会议》
会议日期：1986年
学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学]
摘 要：An attempt was made to improve the durability of GRC with reference to the decline in the strength and drying shrinkage by using the calciumsilicate - C4A3S - slag type cement (hereinafter referred to as CGC), and the influence of alkalinicy and structure of the cement matrix on the characteristics of GRC was studied. CGC produced industrially by Chichibu Cement CO., Ltd. consists mainly of calciumsilicaces (C5S and C2S), calcium aluminate sulfate (C4A3S), calcium sulfate (CS) and water-quenched blast furnace slag. In hydration, calcium silicate hydrate (C-S-H) and ettringite (C3A.3CS.H32) are mainly produced but Ca(OH)2 is not produced, and OH ion concenc ra c ion is very low. These are mentioned as the most salient characteristics of CGC. These characteristics are brought into play as Ca(OH)2 produced from C3S and C2S is consumed in reaction with C4A3S and C5 to produce C3A-3CS-H32 and also in reaction with slag to produce C-S-H. With GRC using CGC in an acrelerative test by means of immersion under water of 70℃, both modulus of rupture (MOR) and Izod impact strength maintained high levels of strength even after immersion for 91 days. With GRC using ordinary portland cement (OPC), the control, both MOR and Izod impact strength declined largely and became almost constant at a low level after immersion for 14 days. A similar tendency was shown under a natural exposure tesc, that is, the decline in strength was insignificant and high energy absorption was maintained with GRC using CGC. With samples using CGC after a bending test, glassfibre remained relatively intact and was observed pulleD out of the matrix on the broken surface. The drying shrinkage of GRC using CGC was about one-fifth of that one using OPC. On the basis of results of measurement of SEM and pore size distribution, the following may be mentioned as the mechanism that prevents the strength of GRC using CGC from declining: 1) Since OH-ion concentration in the matrix is low, the surface of glassfibre i