为研究复合矿物对水泥砂浆早龄期断裂性能的影响，开展4种粉煤灰掺量（0%、15%、30%、45%）和4种纳米偏高岭土（1%、3%、5%、10%）复掺水泥砂浆早龄期（1、3、7、28 d）断裂行为研究。基于三点弯曲实验，分析了水泥砂浆中心缺口梁的荷载-裂缝张开位移曲线、临界裂纹扩展、双K断裂韧度以及断裂能，建立了其抗压强度与断裂韧度和断裂能的关系。研究结果表明：水泥砂浆缺口梁在早龄期的峰值荷载随着粉煤灰（fly ash, FA）质量分数的增加而呈现减小趋势；粉煤灰的掺入不仅降低了砂浆的断裂韧度，而且对失稳韧度的降低具有更为显著的影响。随着粉煤灰掺量的增多，水泥砂浆缺口梁早龄期的断裂能表现出先增大后减小的变化趋势。与纳米偏高岭土复掺后，水泥砂浆缺口梁早龄期的峰值荷载、断裂韧度和断裂能呈现先上升后下降的趋势；1 d龄期时，1%质量分数的纳米偏高岭土（nano-metakaolin, NMK）对峰值荷载提升最大为23.9%；掺加5%纳米偏高岭土时，7 d龄期的断裂能提升效果最大为52.9%。水泥砂浆缺口梁早龄期的起裂韧度、失稳韧度和断裂能随着抗压强度的增加具有线性增加的关系，其相关系数均不低于0.81，与纳米偏高岭土复掺后的相关性要优于单掺粉煤灰。

In order to study the effect of composite minerals on the fracture properties of cement mortar at early age, the fracture behavior of cement mortar compounded with four types of fly ash admixture (0%, 15%, 30%, 45%) and four types of nano-partitioned kaolinite (1%, 3%, 5%, 10%) at early age (1, 3, 7, and 28 d) was carried out. Based on three-point bending experiments, the load-crack opening displacement curves, critical crack extension, double-K fracture toughness, and fracture energy of cement mortar center-notched beams were analyzed, and the relationship between their compressive strength and fracture toughness and fracture energy was established. The results show that the peak load of cement mortar notched beams at an early age shows a decreasing trend with the increase of FA (fly ash) mass fraction; The incorporation of fly ash not only reduces the fracture toughness of mortar but also has a more significant effect on the reduction of the destabilizing toughness. With the increase of fly ash admixture, the fracture energy of cement mortar notched beams at an early age show a tendency of increasing first and then decreasing. The peak load, fracture toughness, and fracture energy of cement mortar notched beams at an early age show a trend of increasing and then decreasing after compounding with nano-partialized kaolin; At the age of 1 day, 1% mass fraction of NMK(nano-metakaolin) enhance the peak load by a maximum of 23.9%; and when 5% nano-partialized kaolin is doped, the effect of the fracture energy enhancement at the age of 7 days is a maximum of 52.9%. The starting cracking toughness, destabilizing toughness, and fracture energy of cement mortar notched beams at an early age had a linear increase with the increase of compressive strength, and their correlation coefficients were not less than 0.81, and the correlation with nano-partialized kaolin was better than that with fly ash alone.