养生条件对掺粉煤灰水泥乳化沥青砂浆收缩及黏弹性能的影响
Effect of curing conditions on shrinkage and viscoelastic properties of fly ash cement emulsified asphalt mortar
陈勇航 1李刚 1赵红艳 1朱文正 1于雪霞 1李文辉1
作者信息
- 1. 石河子大学水利建筑工程学院,新疆 石河子 832000
- 折叠
摘要
水泥乳化沥青砂浆(CA砂浆)性能易受到养生环境和原材料组成的影响,通过设置的 5 组养生条件和 3 种配合比进行 CA砂浆收缩率和动态黏弹性能的测试,并采用扫描电镜观察其微观形貌.结果表明:掺加粉煤灰会适当增大 CA砂浆的膨胀率,不同养生湿度下砂浆体积变化趋势不同,增大沥灰比、升高养生温度均可改善 CA 砂浆的体积稳定性;掺粉煤灰 CA砂浆的储能模量和损耗模量均随养生温度升高而增大,表现为砂浆刚度提高,变形时内部摩擦力做功增加;掺加粉煤灰能够改善 CA 砂浆的黏弹性能,其低温抗开裂性、高温抵抗变形能力均有所增强;20℃干养下粉煤灰 CA砂浆黏弹性能最优;综合收缩性能和黏弹性能,20℃干养下沥灰比为 1.4 的粉煤灰 CA 砂浆性能较优.微观形貌观察的结果显示掺加粉煤灰后 CA 砂浆沥青膜增厚、孔隙率降低、结构更加致密,这是掺加粉煤灰 CA砂浆体积稳定性和黏弹性得以改善的主要原因.
Abstract
The performance of cement emulsified asphalt mortar(CA mortar)is easily affected by the health environment and the composition of raw materials.Using three different mix ratios and five sets of health conditions,the shrinkage and dynamic viscoelastic properties of CA mortar were investigated.A scanning electron microscope was used to examine the microscopic morphology of CA mortar.The results show that the addition of fly ash will appropriately increase the expansion rate of CA mortar.The volume change trend of mortar under different curing wetness is different,increasing the ratio of asphalt to cementitious material and increasing the curing temperature can improve the volume stability of CA mortar.The storage modulus and loss modulus of fly ash CA mortar both increase with the increase of curing temperature.It is manifested as the increase of mortar stiffness and the increase of internal friction work during deformation.The addition of fly ash improves the viscoelastic properties of CA mortar,and its cracking resistance at low temperature and deformation resistance at high temperature are enhanced.The results of loss factor show that the viscoelastic properties of fly ash CA mortar under dry culture at 20℃ are the best.Comprehensive shrinkage and viscoelastic properties,fly ash CA mortar with the ratio of asphalt to cementitious material of 1.4 under dry culture at 20℃ has better performance.The thickening,porosity,and denser structure of the CA mortar asphalt membrane following the addition of fly ash are the primary factors enhancing the volume stability and viscoelastic performance of CA mortar,according to the findings of the microscopic morphological observation.
关键词
水泥乳化沥青砂浆/粉煤灰/养生条件/收缩率/黏弹性Key words
cement emulsified asphalt mortars/fly ash/curing conditions/shrinkage rate/viscoelastic引用本文复制引用
基金项目
新疆生产建设兵团科技攻关项目(2019AB013)
石河子大学自然科学项目(ZZZC201903B)
石河子大学青年创新培育人才项目(CXPY202013)
出版年
2024
NETL
NSTL
万方数据