ZHANG Caili, WANG Ben, LI Tianhao, WANG Yifei, LI Ningli

(School of Civil and Transportation; Tianjin Traffic Engineering Green Material Technology Engineering Center, Hebei University of Technology, Tianjin 300401, China)

Abstract：In order to solve the problem of low-proportion steel slag powder in cement-based composite materials, the impact of activate type, dosage on mechanical properties and microstructure of steel slag powder-cement cementitious materials were studied by mechanical properties test, XRD, SEM, FTIR, etc.The results show that alkali-activator can improve the hydration speed of steel slag powder and increase the compressive strength of the composite cementitious material, but different activators exerts different excitation effects on the cementitious material.The compound activation effect of sodium carbonate and triethanolamine is remarkable.The optimal strength on 3, 7 and 28 d is increased by 47%, 72% and 69%, respectively, comparing with the experimental group without activator.The hydration product type of composite cementitious slurry is not affected by the activator.Triethanolamine has suspension stabilization effect and ability to reduce the surface tension of the solution.Combined with the strong corrosion effect of sodium carbonate, it synergistically strengthens the hydration reaction in the steel slag powder cement system, so that more hydration products are generated in the composite cementitious system and intertwined into a complex and dense spatial structure.

Keywords：steel slag powder；compound activator；compressive strength；hydration mechanism；microscopic characteristics

Received:2022-09-26，Revised:2022-11-05,Online:2023-01-10 16:53。

Funding Project：长安大学重点科研平台开放基金项目，编号：300102210510。

First Author：张彩利(1978—)，女，副教授，博士，硕士生导师，研究方向为路面工程材料。E-mail: zhangcailimeng@163.com。

Corresponding Author:：王犇(1995—)，男，硕士研究生，研究方向为路面工程材料。E-mail: wb17602210485@163.com。