不同碱性环境对转炉钢渣水化和微观结构的影响

不同碱性环境对转炉钢渣水化和微观结构的影响

刘奎生，段劲松，孙建伟^*

（1. 北京城建集团有限责任公司，北京100088；2. 青岛理工大学土木工程学院，山东青岛273400）

摘  要 采用水玻璃激发转炉钢渣制备了“无熟料”胶凝材料，通过改变水玻璃模数而改变碱性环境，采用水化热、XRD、SEM和MIP等方法研究了不同碱性环境对于转炉钢渣水化和微观结构的影响。结果显示：提高水玻璃的模数延迟了碱激发钢渣体系第二个水化放热峰的开始时间，降低了峰值反应速率和累计放热量。改变碱性环境不影响水化产物的类型，且对凝胶产物的平均Ca/Si比和Al/Si比的影响很小。碱激发钢渣的水化产物仍然是C–A–S–H凝胶和Ca(OH)₂，RO相等惰性组分仍然不参与反应。提高水玻璃模数降低了碱激发钢渣体系的水化程度。但当模数较高时，钢渣的水化程度相差不大。提高模数使得反应产物在基体中均匀分布，从而细化了孔隙结构。

关键词  水玻璃；转炉钢渣；水化热；水化产物；微观结构；孔隙结构

中图分类号：TU58⁺2；TU526 

文献标识码：Adoi:10.3969/j.issn.1000-6281.2021.06.008

Effect of different alkaline environment on the hydration and microstructure of converter steel slag

LIU Kui-sheng¹, DUAN Jin-song¹，SUN Jian–wei^2*

(1. Beijing Urban Construction Group Co. Ltd., Beijing 100088；2. School of Civil Engineering，Qingdao University of Technology, Qingdao Shandong 273400，China)

Abstract   The "no clinker " cementing material was prepared by water glass activated converter steel slag. The alkaline environment was changed by changing the modulus of water glass. The effects of different alkaline environment on the hydration and microstructure of converter steel slag were studied by hydration heat, XRD, SEM and MIP. The results show that increasing the modulus of water glass can delay the start time of the second hydration exothermal peak of alkali–activated steel slag, and reduce the peak reaction rate and cumulative heat. The type of hydration products is not affected by changing alkaline environment, and the average Ca/Si ratio and Al/Si ratio of gel are hardly affected. The hydration products of alkali–activated steel slag are C–A–S–H gel and Ca(OH)₂. Inert components such as RO phase do not participate in the reaction. Increasing the modulus of water glass reduces the hydration degree of the alkali–activated steel slag. However, when the modulus is high, the hydration degree of steel slag shows little difference. the reaction products are uniformly distributed in the matrix by increasing the modulus so that the pore structure is refined.

Keywords   water glass; converter slag; hydration heat; hydration product; microstructure; pore structure

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