摘要
为解决高液限土直接用作路堤填料时出现压实困难、水稳定性差等工程问题，通过加州承载比（CBR）试验及现场碾压试验研究高液限土掺砂改良前后压实度、含水率、碾压遍数、CBR值这几个参数间的关系，并从强度衰减和膨胀变形2个方面分析它们的变化规律。研究结果表明：压实度随碾压遍数先显著增加，后小量减小；CBR峰值时的含水率一般大于最佳含水率；高液限土CBR值同时受含水率与压实度所控制，但含水率对高液限土CBR值的影响比压实度更显著；不同膨胀等级造成高液限土掺砂改良前后的CBR值变化特征差异显著；高液限土含水率应控制在ωopt＋2％～ωopt＋6％（ωopt为最优含水率），并采取包边处理及降低压实度标准的措施，可用作下路堤的填料；掺20％砂高液限土含水率应控制在ωopt～ωopt＋6％，可填筑于上下路堤。
To solve engineering problems of compaction difficulty and poor water stability of high liquid limit soil when it was directly used as subgrade filling, the relationship among several parameters of compaction degree, water content, compaction times, and CBR value before and after sand improvement was studied though California bearing ratio test and field rolling test. The change rules were analyzed from two aspects of intensity attenuation and expansion deformation. The results show that compaction degree first increases greatly and then decreases slightly with increasing of compaction times, and water content at maximum CBR value is generally greater than optimal water content. CBR value of high liquid limit soil are controlled by water content and degree of compaction, but the influence of water content on CBR value is more significant than that of compaction degree. Different level of inflation leads to different characteristics of CBR value of high liquid limit soil before and after sand improvement. High liquid limit soil can be used as direct filling material in the upper embankment while water content should be controlled during the range of 2.0% lower and 2.0% higher than the optimum water content after using the surrounding conduction and reducing the standard of degree of compaction. High liquid limit soil modified by 20% sand can be used in upper and lower embankment after water content is controlled during the range of the optimum water content and 6.0% higher than the optimum water content. 2 tabs, 13 figs, 20 refs.
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2016年第1期44-50,共7页
Journal of Chang’an University(Natural Science Edition)
基金
国家自然科学基金项目(51378168)
关键词
道路工程
高液限土
掺砂改良
含水率
压实度
加州承载比
碾压遍数
road engineering
high liquid limit soil
improved by sand
water content
compaction degree
CBR
compaction times
作者简介
戴良军（1963-），男，安徽固镇人，教授级高级工程师，工学博士研究生，E—mail：2765095113@qq．com。
