高原荒漠地区公路路基氯盐渍土改良试验研究  

Experimental Study on Improvement of Chlorine Salinized Soil for Highway Subgrade Construction at Plateau Desert Region

作　　者：周清福 许正璇 ZHOU Qingfu;XU Zhengxuan(China Railway Construction City Construction Investment Co.,Ltd.,NanJing,Jiangsu 210000,China;Qinghai Transportation Planning and Design Research Institute Co. Ltd.,Xining,Qinghai 810000,China)

机构地区：[1]中铁建城市建设投资有限公司,江苏南京210000 [2]青海省交通规划设计研究院有限公司,青海西宁810000

出　　处：《公路工程》2022年第3期112-117,共6页Highway Engineering

基　　金：青海省交通科技项目(2018-SF-139)。

摘　　要：在高原荒漠地区某公路建设现场采取了氯盐渍土,制备了不同水泥、水泥窑粉尘(CKD)配比的改良土试样,开展了击实试验、UCS试验、CBR试验等,获取了不同改良剂掺量下改良土物理力学指标的变化规律,并分析了干湿循环和冻融循环对力学指标的影响,探讨了采用水泥+CKD改良此地区盐渍土的可行性。研究表明,同时掺入水泥和CKD时,随着CKD掺量增加,改良盐渍土的最大干密度总体呈减小趋势,UCS的提升十分明显;在掺入水泥3%的前提下,加入9.1%和17.2%的CKD可以使改良土的CBR值分别达到下路堤和上路堤的填筑要求,经济成本相对单独水泥改良更低,而且掺入CKD还可以明显提高耐久性;最终根据一系列试验结果,给出了该路段针对上路堤和下路堤的盐渍土改良配比建议。This studycollected chlorine salinized soil at a certain highway construction site in plateau desert region.Improved soil specimens with different cement and cement kiln dust(CKD)ratio were prepared.A series tests,such as compaction test,UCS test and CBR test,were carried out.The variation rule of physical and mechanical indexes with different dosages of improver was acquired.The effect on physical and mechanical indexes from dry-wet cycle and freezing-thawing cycle was analyzed.The feasibility of using cement+CKD to improve chlorine salinized soil in this region was discussed.The research shows that when cement and CKD are added at the same time,the maximum dry density of improved saline soil generally decreases with the increase of CKD content,and UCS is significantly increased.Based on adding 3%cement,adding 9.1%and 17.2%CKD can respectively make the CBR of the improved soil meet the requirements of lower embankment and upper embankment,with lower economic cost than using cement alone.Moreover,the durability can also be improved obviously by adding CKD.Finally,according to a series of test results,the improvement ratio for lower embankment and upper embankment is proposed.

关 键 词：公路路基 氯盐渍土 水泥窑粉尘 无侧限抗压强度 CBR值 

分 类 号：U416.166[交通运输工程—道路与铁道工程]