次生盐渍化对西非滨海细砂填料路用性能的影响  

The impact of secondary salinization on the road performance of West African coastal fine sand fill materials

作　　者：谭鹏 沈亚斌 鞠志成 高波 蒋勇 刘军勇[2] TAN Peng;SHEN Yabin;JU Zhicheng;GAO Bo;JIANG Yong;LIU Junyong(China Highway and Bridge Corporation,Beijing 100011,China;National Key Laboratory of Green and Long-Life Road Engineering in Extreme Environment,CCCC First Highway Consultants Co.,Ltd.,Xi′an 710075,Shaanxi,China)

机构地区：[1]中国路桥工程有限责任公司,北京100011 [2]中交第一公路勘察设计研究院有限公司极端环境绿色长寿道路工程全国重点实验室,陕西西安710015

出　　处：《水利水电技术(中英文)》2024年第S2期711-716,共6页Water Resources and Hydropower Engineering

基　　金：中国路桥工程有限责任公司科技研发项目(P2220449)

摘　　要：为探明次生盐渍化对滨海细砂填料路用性能的影响规律,依托塞内加尔MK高速公路项目,进行不同含水率、含盐量、浸水时间下的路堤填料击实和承载比试验。试验结果表明:当含盐量较低时,受颗粒级配影响,非洲滨海细砂的击实曲线呈现出双峰特征,且含水率较低时,干密度最大;随着含盐量的逐步增加,击实曲线逐渐变为单峰形态,最大干密度也有所提高。盐渍化细砂填料的CBR值与盐份晶体溶解难易程度密切相关,当压实度为93%时,试件颗粒间相对疏松,盐份晶体可以快速溶解,CBR值随着盐渍化程度增大不断降低,最大降幅约40%;当压实度提高为95%和97%后,试件更加密实,使得内部盐份晶体溶解受阻,填料CBR值则呈现出先增大后减小的趋势,且压实度越高,降低幅度越小。为保证工程质量及后期运营安全,对于塞内加尔滨海细砂路堤填料,压实度不宜小于95%,且应做好防排水措施。In order to explore the impact of secondary salinization on the road performance of coastal fine sand filling materials,experiments were conducted on the compaction and bearing ratio of embankment filling materials under different moisture content,salt content,and immersion time based on the MK highway project in Senegal.The test result showed that when the salt content was low,the compaction curve of African coastal fine sand showed a bimodal feature due to the influence of particle size distribution,and the dry density was highest when the moisture content was low;As the salt content gradually increases,the compaction curve gradually changes to a single peak shape,and the maximum dry density also increases.The CBR value of saline fine sand filler is closely related to the difficulty of salt crystal dissolution.When the compaction degree is 93%,the particles in the specimen are relatively loose,and the salt crystals can dissolve quickly.The CBR value decreases continuously with the increase of saline degree,with a maximum decrease of about 40%;When the compaction degree increases to 95%and 97%,the dissolution of salt crystals inside the specimen is hindered,and the CBR value of the filler shows a trend of first increasing and then decreasing.Finally,in order to ensure the quality of the project and the safety of later operation,the compaction degree of the Senegal coastal fine sand embankment filling should not be less than 95%,and waterproof and drainage measures should be taken.

关 键 词：路基工程 滨海细砂 击实性能 CBR 盐渍土 

分 类 号：U416.1[交通运输工程—道路与铁道工程]