不同初始状态下压实粉土的CBR试验研究  

Study on CBR Test of Compacted Silt with Different Initial Condition

作　　者：杨晶[1,2] 马富丽[1] 闫嘉庆[1] 白晓红[1] 

机构地区：[1]太原理工大学建筑与土木工程学院,太原市030024 [2]山西大学工程学院土木工程系,太原市030013

出　　处：《公路》2013年第12期161-165,共5页Highway

基　　金：国家自然科学基金;项目编号51178287;山西省自然科学基金;项目编号2010011029;山西省回国留学人员科研资助项目;项目编号2011-026

摘　　要：粉土工程性质不良,粉土填筑路堤的强度和稳定性与不同压实状态下粉土的工程力学性质息息相关。为评价粉土路基强度,针对路基粉土的工程力学特性,对不同初始状态下的压实粉土试样进行了击实试验和CBR(承载比)试验,分析不同初始含水量下的粉土在不同击实次数下击实后的力学性能,探讨击实次数相同时压实粉土CBR值随初始含水量变化的关系以及初始含水量相同时压实粉土CBR值随击实次数的关系。比较了相同初始状态的压实粉土浸水和不浸水CBR强度的差异。研究结果表明,击实次数相同的压实粉土试样不浸水CBR值随初始含水量增大而减小,浸水CBR值随初始含水量变化出现峰值,峰值含水量基本上与该击实次数下的最优含水量一致。初始含水量越低,试样浸水前后的CBR值变化越大,试样接近饱和时,浸水和不浸水CBR值基本没有差异。各初始含水量下的压实粉土试样其CBR值随击实次数变化没有特定的规律性,与初始含水量的大小有关。The engineering properties of silt is poor. The stability and strength of silt embankment is closely associated with the engineering properties of silt under different compaction condition. In order to evaluate the strength of silt embankment and the engineering mechanical properties of compacted silt under different initial condition, a series of laboratory experiments such as compaction tests, CBR （California Bearing Ratio） tests are studied. The mechanics of series of silt with different initial water content and compaction times are analyzed. The relationship between CBR values and the initial water content is discussed under a certain compaction times. Also, the relationship between CBR values and compaction times is discussed under a certain initial water content. The differences between CBR values of soaking compacted silt and un-soaking status are compared. It is found that un-soaking CBR values of compacted silt under a certain compaction times decreases with the increase of initial water content. There is a peak value on the curves of soaking CBR values and initial water contents, and the peak value is keeping with the optimum water content under a certain compaction times. The soaking CBR values change more when the initial water content is lower. When the specimen is close to saturation, there is mainly no difference between soaking and un-soaking CBR Value. There have no specific regularity between CBR values and compaction times when the compacted silt specimen with a certain initial water content. It is connected with the value of initial water content.

关 键 词：初始含水量 击实次数 压实粉土 CBR 强度 

分 类 号：U414.103[交通运输工程—道路与铁道工程]