添加外加剂的水泥粉煤灰基层结合料性能研究

Performance of Cement and Fly Ash Base Course Binder with Chemical Activator

在水泥和粉煤灰配比为1∶2条件下,以无侧限抗压强度、劈裂强度、抗弯拉强度和弯拉模量为指标,研究N型激活剂和U型膨胀剂的外掺形式和掺量;采用SEM观察掺化学外加剂水泥粉煤灰结合料的结构和形貌,分析其水化机理。研究表明:N型激活剂可以提高粉煤灰的活性,U型膨胀剂可以有效提高结合料的抗裂性能;外掺2%N型激活剂、3%U型膨胀剂的水泥粉煤灰稳定基层结合料具有较好的力学性能和抗裂性能。

When the proportion of cement and fly is 1：2, the external addition method and dosage of N-type activator and U- type expansion agent were studied by taking account of different indexes, such as unconfined compressive strength, cleavage strength, flexural tensile strength and flexural tensile modulus. The Structure and morphology of cement and fly ash binder were obsetwed by means of SEM to analyze the hydration mechanism of the binder. The results show that N-type activator could significantly increase fly ash activity and U-type activator could improve crack resistance of mixture. The cement and fly ash stabilized base course binder with 2% N-type activator and 3% U-type activator have good mechanical properties and crack resistance.