通过掺入聚醚型减缩剂（PSRA）改善碱激发矿渣-铜渣砂浆（CSM）的体积稳定性，研究了PSRA掺量对CSM凝结时间、抗压强度和干燥收缩率的影响，并采用等温量热仪、X射线衍射仪、扫描电镜-能谱仪、核磁共振和热重-差示量热分析仪等分析了PSRA对CSM水化进程和微观结构影响，探讨了PSRA的减缩机理.结果表明：PSRA的掺入延长了CSM净浆的凝结时间，延缓了体系的水化进程，且延缓作用随着PSRA掺量的增大而增强；PSRA掺量为0%~2.0%时，CSM的干燥收缩率和抗压强度均随着PSRA掺量的增大而逐渐减小；PSRA降低了孔溶液的表面张力，改变了孔结构，使得毛细管压力下降，进而起到减小CSM干燥收缩的效果.

The volume stability of alkali-activated slag-copper slag mortar（CSM） was improved by incorporating polyether-type shrinkage reducing admixture（PSRA）. The effects of PSRA content on the setting time， compressive strength and drying shrinkage of CSM were investigated. The hydration process and microstructure of CSM were studied by isothermal calorimetry， X-ray diffractometer， scanning electron microscopy-energy dispersive spectrometer， nuclear magnetic resonance and thermogravimetric-differential scanning calorimetry. The shrinkage reduction mechanism of SRA was explored. The results show that the incorporation of PSRA extends the setting time of CSM slurry， and delays the hydration process of the system， with the delaying effect increasing as the PSRA content increases. When the PSRA content ranges from 0% to 2.0%， both the drying shrinkage and compressive strength of CSM gradually decrease with the increase of PSRA content. PSRA reduces the surface tension of the pore solution and changes the pore structure， resulting in a decrease in capillary pressure and thus reducing drying shrinkage of CSM.

TQ172

国家自然科学基金资助项目（52308227）