摘要
为了快速有效地检测路基分层压实度,以黄土路基为例,提出通过液压夯实机的夯击补强作用来检测路基分层压实度的思路。基于分层压实理论,建立液压夯实的基本模型并推导了夯前和夯后分层压实度的关系,设计并开展液压夯实足尺模型试验。研究结果表明:深度超过约1.5 m时,压实效果可以忽略;路基分层界面沉降量和表层夯沉量具有阶段性变化特征,分别以0.8~1.2 m和6~9击为界限。引入有效压实深度的概念并建立其回归公式;采用回归方法得到了表层夯沉量、有效压实深度和分层界面沉降量之间的玻尔兹曼函数关系;采用线性回归方法得到了夯后分层压实度与分层界面沉降量及表层夯沉量之间的关系;推导出夯前路基分层压实度计算公式,形成了黄土路基补强分层压实度检测方法。将液压夯实法运用于实体工程,其计算结果和灌砂法检测结果的误差在2%以内。
In order to obtain the layer compactness of subgrade more quickly and effectively,this paper took loess subgrade as an example,and proposed the idea of detecting the subgrade layer compactness achieved by the hydraulic compactor.Based on the theory of layered compaction,the basic model of hydraulic compaction was established and the relationship between the initial layered compactness and the compacted layered compactness was deduced.A full-scale model test of hydraulic compaction was designed and carried out.The results show that the compaction effect can be ignored when the depth is more than about 1.5 m.The layered interface settlement of subgrade and ground settlement have the characteristics of stage change,which are bounded by 0.8~1.2 m and 6~9 tamping times respectively.The concept of improvement depth was introduced and its regression formula was established.The Boltzmann function relationship among ground settlement,improvement depth and layered interface settlement was obtained by regression method.The relationship among compacted layered compactness,layered interface settlement and ground settlement was obtained by linear regression method.The calculation formula of the initial layered compactness of subgrade was deduced and the method for detecting the compactness of loess subgrade was formed.The hydraulic compaction method was applied in a practical project,and the error between the calculation result and the detection result of sand filling method was within 2%.
作者
周志军
张志鹏
郭涛
徐天宇
ZHOU Zhijun;ZHANG Zhipeng;GUO Tao;XU Tianyu(School of Highway,Chang’an University,Xi’an 710064,China;Xi’an Highway Engineering Testing Center,Xi’an 710064,China;CCECC Fuzhou Survey&Design Institute Co.,Ltd.,Fuzhou 350013,China)
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2020年第12期3052-3062,共11页
Journal of Railway Science and Engineering
基金
国家自然科学基金资助项目(51878064)。
关键词
道路工程
黄土路基
液压夯实法
模型试验
有效压实深度
Road engineering
loess subgrade
hydraulic compaction method
model test
improvement depth
