Applicability of high carbon ferrochromium slag as an aggregate for ultra high strength concrete

高碳铬铁渣作为超高强混凝土骨料的适用性

• 批准号: 09555135
• 负责人: KAWAMURA Mitsunori
• 金额: $ 8万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-09555135/
• 关键词: high carbon ferrochromium slag; high strength concrete; RPC; late hydration; expansive pressure; volume stability; hydrothermal; tobermorite; 微粉石英; 熱処理; オートクレーブ; ポロシティー; ゾノトライト; 空隙率; 自己収縮; 超高強度コンクリート; シリカフューム; 微視的構造

In order to use high carbon ferrochromium slag as an aggregate for ultra high strength concrete, mineralogical compositions of the slag and its alkali reactivity in cementitious matrix are investigated. Effects of its reactivity and surface texture on mechanical properties of high strength mortars and RPC (Reactive Powder Concrete : ultra high strength concrete) were investigated in terms of characteristic microstructures and microscopic failures. The major outcomes in this study are as follows.(1) The high carbon ferrochromiurn slag has the potential reactivity with cement paste matrix.(2) The reaction of the slag with alkaline cement matrix does not result in the deterioration of concrete due to alkali silica reaction.(3) The reaction and rough texture of the slag particles contribute to the increase in bond strength and crack growth resistance.(4) When silica fume mortars with an extremely low water/binder ratio were cured in water, shrinkage and swelling occurred simultaneously.(5) Generation of internal expansive pressure due to the late cement hydration should be taken into account as a mechanism to cause maicrocracks in mortars with low water/binder ratios.(6) The slag can be used as an aggregate for ultra high strength concrete. However, the optimum mix proportion and the thermal treatment for the concrete with the slag may be different than those for concretes with natural aggregates. Dissolution of silica in the slag affects the growth of crystalline reaction products and their morphology.

为了将高碳铬铁渣用作超高强混凝土的骨料，研究了高碳铬铁渣的矿物组成及其在胶凝基质中的碱活性。从微观结构特征和微观破坏两方面研究了高强砂浆和RPC(活性粉末混凝土：超高强混凝土)的反应活性和表面纹理对其力学性能的影响。本研究的主要结果如下：(1)高碳铬渣与水泥净浆基质具有潜在的反应活性。(2)矿渣与碱性水泥基质的反应不会导致混凝土因碱硅反应而劣化。(3)矿渣颗粒的反应和粗糙的质地有助于提高粘结强度和抗裂缝扩展能力。(4)在水中养护极低水胶比的硅灰砂浆时，收缩和膨胀同时发生。(5)水泥后期水化产生的内部膨胀压力是低水胶比砂浆产生微裂缝的机理。(6)矿渣可用作超高强混凝土的集料。然而，矿渣混凝土的最佳配合比和热处理方式可能与天然骨料混凝土有所不同。渣中二氧化硅的溶解影响结晶反应产物的生长和形态。

项目成果

Kubo, R.H., Igarashi, S., Kawamura, M.: "Long-term volume changes and microcracks formation in high strength mortars (in Japanese)"Concrete Research and technoloy. Vol.11, No.3. 71-76 (2000)

Kubo, R.H.、Igarashi, S.、Kawamura, M.：“高强度砂浆中的长期体积变化和微裂纹形成（日语）”混凝土研究和技术。

Igarashi, S., Kawamura, M., Arano, N., Kawaguchi, S: "Alkali reactivity of high carbon ferrchromium slag and its applicability as an aggregate for concrete"Proc.of the 10th Intl.Conf.on the Chemistry of Cement, Gothenburg. Vol. 4. 4iv051 (1997)

Igarashi, S.、Kawamura, M.、Arano, N.、Kawaguchi, S：“高碳铬铁渣的碱反应性及其作为混凝土骨料的适用性”第十届国际水泥化学会议论文集

Igarashi, S., Kawamura, M.: "Microstructure and strength of RPC produced at different curing temperatures (in Japanese)"Cement Science and Concrete Technology. No.54 (in press). (2000)

Igarashi, S., Kawamura, M.：“不同固化温度下生产的 RPC 的微观结构和强度（日语）”《水泥科学与混凝土技术》。

Igarashi, S., Kawamura, M., Watanabe, A.: "Evaluation of pore size distributions in mortars by SEM image analysis (in Japanese)"Proc.of the Japan Concrete Institute. Vol.22, No.2. 697-702 (2000)

Igarashi, S.、Kawamura, M.、Watanabe, A.：“通过 SEM 图像分析评估砂浆中的孔径分布（日语）”日本混凝土研究所的论文。

Shin-ichi Igarashi,Mistunori Kawamura Noriyuki Arano,Sotoaki Kawaguchi: "Alkali Reactivity of High-Carbon Ferrochromium Slag and Its Applicability as Aggregate for Concrete" Proc.of the 10th Intl.Conf.on Chemistry of Cement. Vol.4. 4iv051 (1997)

Shin-ichi Igarashi、Mistunori Kawamura Noriyuki Arano、Sotoaki Kawaguchi：“高碳铬铁渣的碱反应性及其作为混凝土骨料的适用性”第十届国际水泥化学会议论文集。