级配对低剂量水泥改性级配碎石性能的影响  

Effect of gradation on performance of low-dose cement modified graded gravel

作　　者：周志刚[1] 王梓龙 蒋少稀 ZHOU Zhi-gang;WANG Zi-long;JIANG Shao-xi(Key Laboratory of Road Structure and Material, Ministry of Transport of PRC, Changsha University of Science and Technology, Changsha 410114,China)

机构地区：[1]长沙理工大学道路结构与材料交通行业重点试验室,湖南长沙410114

出　　处：《长沙理工大学学报（自然科学版）》2018年第4期9-16,共8页Journal of Changsha University of Science and Technology:Natural Science

基　　金：国家自然科学基金资助项目(51378084);广西交通科技计划项目(桂交综合发[2010]109号)

摘　　要：为了探讨级配对低剂量水泥改性级配碎石性能的影响,促进低剂量水泥改性级配碎石基层结构的推广应用,参照相关规范中水泥稳定碎石和级配碎石的级配范围,选择了4种具有代表性的级配制备低剂量水泥改性级配碎石,进行了无侧限抗压强度、抗压回弹模量及CBR试验,干缩和温缩试验,液塑限和渗水试验,对比分析了不同级配的低剂量水泥改性级配碎石的路用性能及其随龄期的变化规律。研究结果表明,级配对低剂量水泥改性级配碎石路用性能具有明显的影响,粗集料偏多会降低无侧限抗压强度和抗压回弹模量,而细集料偏多会降低CBR值;级配对干缩性能与温缩性能的影响具有相似规律,增加粗集料、减少细集料,有利于控制碎石基层收缩裂缝的产生;无论哪种级配,低剂量水泥改性级配碎石均具有良好的渗水性能和水稳定性。综合比较,宜选择粗细集料均具有一定含量的骨架密实型级配用于低剂量水泥改性级配碎石。In order to study the effect of gradation on the performance of low-dose cement modified graded gravel,and to promote the popularization and application of low-dose cement modified graded gravel base structure,four representative gradations are selected for preparation of low-dose cement modified graded gravel with reference to the grading range of cement stabilized macadam and graded gravel in the relevant specifications.To compare and analyze the road performance of low-dose cement modified graded gravel with different gradations and its variation rule with age,the unconfined compressive strength,compressive rebound modulus and CBR test,dry shrinkage test and temperature shrinkage test,liquid-plastic limit test and water seepage test were carried out.The results show that the gradation has obvious influence on the road performance of low-dose cement modified graded gravel.The excessive coarse aggregate will reduce the unconfined compressive strength and the compressive rebound modulus,while the fine aggregate will reduce the CBR value.The effects of gradation on dry shrinkage and temperature shrinkage are similar to each other.Increasing coarse aggregate and reducing fine aggregate are beneficial to control the shrinkage crack in gravel base.No matter what kind of gradation,low-dose cement modified graded gravel has good performance on water permeability and water stability.In summary,it is suitable to select skeleton dense gradation with certain content of coarse and fine aggregate for low dose cement modified graded gravel.

关 键 词：低剂量水泥改性级配碎石 级配 龄期 力学性能 收缩性能 渗水性能 水稳定性能 

分 类 号：U416.217[交通运输工程—道路与铁道工程]