摘要
戈壁盐渍土地区具有年温差较大、集料和拌合用水含盐量高等特征。为了分析温度、硫酸盐含量对水稳碎石击实特性的影响,首先通过击实试验分析了温度、硫酸钠含量对最佳含水率、最大干密度影响。其次,采用极差法分析了温度、硫酸钠含量对最大干密度的影响程度。基于此,通过SEM电镜扫描试验分析了击实后水稳碎石的微观结构。结果表明:温度<32.4℃且逐渐减小,最大干密度减小,最佳含水率增大;温度>32.4℃且逐渐增大,最大干密度增大,最佳含水率减小。硫酸钠含量增大,水稳碎石湿润性减小,最大干密度减小,最佳含水率增大;极差分析表明最大干密度受温度(0.055)影响比硫酸钠含量(0.016)大;温度>32.4℃,水稳碎石结构密实,孔隙最少,易击实;温度<32.4℃且逐渐减小,水稳碎石结构复杂,难击实。因此温度、硫酸钠含量可通过改变硫酸钠3种状态(Na_(2)SO_(4)溶液、Na_(2)SO_(4)·10H_(2)O、无水Na_(2)SO_(4)晶体)所占比例来改变水泥稳定碎石基层材料击实特性变化规律,从而影响基层材料压实质量。
Gobi saline soil area has the characteristics of large annual temperature difference,high salt content of aggregates and mixing water.In order to analyze the influence of temperature and sulfate content on the compaction characteristics of cement stabilized macadam,firstly,the heavy compaction test was used to analyze the influence of temperature and sodium sulfate content on the optimal moisture content and maximum dry density of cement stabilized macadam base material;secondly,the range method was used to analyze the influence of temperature and sodium sulfate content on the maximum dry density;based on this,the microstructure characteristics of cement stabilized macadam base materials after compaction were analyzed by SEM test.The results show when the temperature is less than 32.4℃and decreases gradually,the maximum dry density decreases,and the optimum moisture content increases;when the temperature is higher than 32.4℃and increases gradually,the maximum dry density increases and the optimum moisture content decreases.With the increase of sodium sulfate content,the wettability of the material and the maximum dry density decreases,but the optimum moisture content increases;the maximum dry density affected by temperature(0.055)was greater than that affected by sodium sulfate content(0.016);when the temperature is higher than 32.4℃,the structure of cement stabilized macadam is dense and easy to be compacted due to the least pores;when the temperature is lower than 32.4℃and decreases gradually,it is difficult to compact due to the existence of cement stabilized macadam reticular structure.Therefore,the temperature and sodium sulfate content can change the proportion of three states of sodium sulfate(sodium sulfate solution,Na_(2)SO_(4)·10H_(2)O,and anhydrous sodium sulfate crystal)to affect the variation of compaction characteristics of cement stabilized macadam base materials,thus affecting the compaction quality of base materials.
作者
范渊博
魏芳
吴谦
唐可
张巨
FAN Yuanbo;WEI Fang;WU Qian;TANG Ke;ZHANG Ju(The Construction Management Office of Beiyingen—Lujing Section of the G331,Alxa League,Nei Mongol 750300,China;The Construction Management Office of Bayannuorigong to Yabulai First-class Highway of G307,Alxa League,Nei Mongol 750300,China;School of Highway,Chang′an University,Xi′an,Shaanxi 710064,China)
出处
《公路工程》
2023年第2期128-135,共8页
Highway Engineering
基金
内蒙古自治区交通运输厅科技项目(NJ-2019-23)
中央高校基本科研业务专项资金项目(300102219108)。
关键词
水泥稳定碎石
击实特性
极差分析
SEM电镜
cement stabilized macadam
compaction properties
range analysis
SEM test
