Alkali-activated slag (AAS) is a green and environmentally friendly cementitious material, but its poor toughness and volume stability limit the practical application. Due to the flexibility and weathering resistance, SAE is widely used to promote the toughness of cementitious materials. Thus, SAE could be a potential additive in AAS system to improve the toughness and volume stability. In this work, different dosages of SAE were used to improve toughness and volume stability of AAS system. The toughness of AAS was evaluated by mechanical F/C ratio and fracture energy. The volume stability was characterized by one-dimensional drying shrinkage test and two-dimensional plate cracking test. The results indicated that the addition of 10 wt% SAE could enhance the F/C ratio (by 120.0%) and the fracture energy (by 242.3%) of AAS at 28 days, and this promotion of toughness could be attributed to physical adhesion and chemical bonding between SAE and hydration products. 5 wt% SAE could also reduce the drying shrinkage rate (by 10.3%) and crack area (by 99.4%) at 28 days, and the improvement of volume stability was due to the refinement effect of SAE on pore structure of AAS. This study provides a reference for the systematic evaluation method for the toughness and volume stability of AAS, and offers guidance for the application of SAE in AAS.

碱活化渣（AAS）是一种绿色环保的胶凝材料，但其韧性和体积稳定性较差，限制了实际应用。由于柔韧性和耐候性，SAE被广泛用于提高胶凝材料的韧性。因此，SAE 可以成为 AAS 系统中提高韧性和体积稳定性的潜在添加剂。在这项工作中，不同剂量的 SAE 用于提高 AAS 系统的韧性和体积稳定性。AAS的韧性通过机械F/C比和断裂能来评价。体积稳定性以一维干燥收缩为特征试验和二维板开裂试验。结果表明，添加 10 wt% SAE 可以提高 AAS 在 28 天时的 F/C 比（提高 120.0%）和断裂能（提高 242.3%），而这种韧性的提高可以归因于物理粘附和SAE和水合产物之间的化学键合。5 wt% SAE 还可以降低 28 天的干燥收缩率（10.3%）和裂纹面积（99.4%），体积稳定性的提高是由于 SAE 对 AAS 孔结构的细化作用。本研究为AAS韧性和体积稳定性的系统评价方法提供参考，为SAE在AAS中的应用提供指导。