Conformability of Aggregate in Concrete and Alkali Silica Reaction Products

本文的研究成果分为矿物外加剂抑制ASR的机理、钙（OH）2在ASR凝胶组成中的影响、锂盐对ASR凝胶组成的影响以及超高强度混凝土中的ASR。每个主题所揭示的项目总结如下：(1)即使在含粉煤灰砂浆中也会产生无膨胀的ASR凝胶。(2)含jmprars，对/OH^-离子浓度的降低幅度不大，抑制砂浆中ASR膨胀是由于降低了离子和孔隙溶液通过水泥浆相的流动性。(3)在含硅灰砂浆中，抑制ASR膨胀是由于孔隙溶液中OH^-离子浓度的大幅降低。(4)孔隙溶液在砂浆中煅烧的燧石骨料颗粒中向裂缝内部渗透，并沿裂缝中的二氧化硅表面发生ASR。(5)通过添加锂盐均匀化ASR凝胶的组成。然而，ASR凝胶中的均质化可能与ASR的抑制没有直接关系。(6)在水灰比极低的砂浆中，活性骨料颗粒内部产生的ASR凝胶不能渗透到水泥浆体中，而是在水泥浆体内部的裂缝中积累。

The achievements obtained in this study are divided into the four themes of ASR suppression mechanisms of mineral admixtures, irples of Ca(OH)2 in ASR gel composition, effects of lithium salts on ASR gel compositions and ASR in ultra-high strength concrete. The items revealed in each theme are summarizedas follows ;(1) ASR gels were found to be produced even in fly ash-containing mortars showing no expansion.(2) Iri blastfurnaceTContaining jmprtars, reductions in/OH^- ion concentration are not so great, and the suppression of ASR expansion in the mortars is due to the reduction in the mobility of ions and pore solution through the cement paste phase.(3) In silica fume-containing mortars, the suppression of ASR expansion is, brought about by great reductions in OH^- ion concentration in, the pore solution.(4)The pore solution intnided into fissures in the cacined flint aggregate particles in mortars, and then ASR occurred along silica surfaces in the fissures.(5)The composition of ASR gels was homogenized by the addition of lithium salts. However, the homogenization in the ASR gels may not directly be related to the suppression of ASR.(6) In mortars with, an extremely low water : cement ratio, ASR gels produced within reactive aggregate particles could not permeate into the cement paste, and were accumulated in cracks within the cement paste.