真空脱水快速评估碱激发矿渣的收缩性能及机理研究

doi:10.16552/j.cnki.issn1001-1625.2026.0012

摘要/Abstract

摘要：

针对碱激发矿渣（AAS）收缩率大、现有测试方法周期长的问题，本研究采用真空脱水技术快速评价其收缩性能，研究真空脱水温度（40、50、60 ℃）对AAS收缩性能与微观结构的影响机制。通过监测AAS内部相对湿度与孔溶液表面张力的动态变化，结合多尺度微观分析技术，揭示了温度-水分迁移-结构演化的耦合规律。结果表明，真空脱水显著改变了AAS的收缩进程，AAS早期收缩加速，28 d总收缩率显著降低，其中40 ℃处理后的减缩效果最佳。适度升温（40~50 ℃）可促进游离水脱除并优化孔隙结构，增大的毛细管压力在AAS材料早期黏塑性阶段通过孔径优化-蠕变耗散协同作用有效降低了收缩应力；然而，温度过高（60 ℃）会导致毛细管压力积累速率超过蠕变耗散能力，引起应力-应变失配，进而诱发微裂纹与增加孔隙率。

关键词: 碱激发矿渣, 真空脱水, 快速收缩评价, 蠕变效应, 毛细管压力, 孔隙结构

Abstract:

Aiming at the problems of large shrinkage rate and long test cycle of alkali-activated slag （AAS）， this study used vacuum dehydration technology to quickly evaluate its shrinkage performance， and studied the influence mechanism of vacuum dehydration temperature （40， 50， 60 ℃） on the shrinkage performance and microstructure of AAS. By monitoring the dynamic changes of AAS internal relative humidity and pore solution surface tension， combined with multi-scale microscopic analysis technology， the coupling law of temperature-moisture migration-structure evolution was revealed. The results show that vacuum dehydration significantly changes the shrinkage process of AAS. The early shrinkage of AAS is accelerated， and the total shrinkage rate at 28 d is significantly reduced. The shrinkage reduction effect after 40 ℃ treatment is the best. Moderate temperature rise （ 40 to 50 ℃） can promote the removal of free water and optimize the pore structure. The increased capillary pressure can effectively reduce the shrinkage stress in the early viscoplastic stage of AAS material through the synergistic effect of pore size optimization and creep dissipation. However， too high temperature （60 ℃） will cause the capillary pressure accumulation rate to exceed the creep dissipation capacity， causing stress-strain mismatch， which in turn induces microcracks and increases porosity.

Key words: alkali-activated slag, vacuum dehydration, rapid shrinkage evaluation, creep effect, capillary pressure, pore structure

中图分类号:

TQ177

田成龙, 陶圆, 刘乐平, 相继春, 崔学民, 贺艳. 真空脱水快速评估碱激发矿渣的收缩性能及机理研究[J]. 硅酸盐通报, 2026, 45(7): 2379-2388.

TIAN Chenglong, TAO Yuan, LIU Leping, XIANG Jichun, CUI Xuemin, HE Yan. Rapid Assessment of Shrinkage Performance and Its Mechanism of Alkali-Activated Slag via Vacuum Dehydration[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2026, 45(7): 2379-2388.

图/表 12

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Sample	Activator	Na₂O content/%	W/B	Dehydration time/h	Temperature/℃
NH-CG	NaOH	5	0.35	—	—
NH-VD-40				6，12，18，24	40
NH-VD-50				6，12，18，24	50
NH-VD-60				6，12，18，24	60
WG-CG	Waterglass			—	—
WG-VD-40				6，12，18，24	40
WG-VD-50				6，12，18，24	50
WG-VD-60				6，12，18，24	60

Sample	Activator	Na₂O content/%	W/B	Dehydration time/h	Temperature/℃
NH-CG	NaOH	5	0.35	—	—
NH-VD-40				6，12，18，24	40
NH-VD-50				6，12，18，24	50
NH-VD-60				6，12，18，24	60
WG-CG	Waterglass			—	—
WG-VD-40				6，12，18，24	40
WG-VD-50				6，12，18，24	50
WG-VD-60				6，12，18，24	60

Sample	Surface tension/（mN·m^-1）
Sample	0 h	6 h	12 h	18 h	24 h
NH-CG	59.4	55.1	44.8	40.4	39.6
NH-VD-40	59.4	48.8	45.4	48.4	53.8
NH-VD-50	59.4	54.0	57.7	53.8	56.9
NH-VD-60	59.4	62.5	59.4	57.9	52.5
WG-CG	47.0	46.7	41.9	42.2	51.0
WG-VD-40	47.0	49.3	48.2	46.9	52.7
WG-VD-50	47.0	48.4	47.6	45.0	54.5
WG-VD-60	47.0	53.9	49.3	47.3	41.5

Sample	Surface tension/（mN·m^-1）
Sample	0 h	6 h	12 h	18 h	24 h
NH-CG	59.4	55.1	44.8	40.4	39.6
NH-VD-40	59.4	48.8	45.4	48.4	53.8
NH-VD-50	59.4	54.0	57.7	53.8	56.9
NH-VD-60	59.4	62.5	59.4	57.9	52.5
WG-CG	47.0	46.7	41.9	42.2	51.0
WG-VD-40	47.0	49.3	48.2	46.9	52.7
WG-VD-50	47.0	48.4	47.6	45.0	54.5
WG-VD-60	47.0	53.9	49.3	47.3	41.5

Item	NH-CG	NH-VD-40	NH-VD-50	NH-VD-60	WG-CG	WG-VD-40	WG-VD-50	WG-VD-60
Calcite content/%	46.23	48.28	52.35	58.34	45.09	58.82	61.14	57.82
Hydrotalcite content/%	1.15	1.29	1.42	1.33	0.09	0.21	0.31	0.40