基于加州承载比的改性路基土路面铺装厚度与施工深度优化研究  

Research on the Optimization of Pavement Thickness and Construction Depth of Modified Subgrade Soil Based on the California Bearing Ratio

作　　者：周明浩 ZHOU Minghao(Beijing No.1 Municipal Construction Engineering Co.,Ltd.,Beijing 100083,China)

机构地区：[1]北京市市政一建设工程有限责任公司,北京100083

出　　处：《施工技术（中英文）》2024年第21期109-113,142,共6页Construction Technology

摘　　要：基于加州承载比开展改性路基土路面铺装厚度与施工深度优化研究,制备3种不同质量比(25%膨胀土+75%高岭土、35%膨胀土+65%高岭土、75%膨胀土+25%高岭土)路基土,并对路基土进行化学处理(20%水泥+8%石灰),通过阿特伯格极限试验、普罗克特压实试验、加州承载比试验和膨胀试验,研究路基土工程特性。研究结果表明,未改性路基土液限、塑限、塑性指数、含水率和膨胀率均随着膨胀土含量的增加有所提高;未改性路基土加州承载比不满足规范限值要求,改性路基土加州承载比明显增大,满足道路工程建设要求;改性路基土减小了路面铺装厚度和施工深度,其中25%膨胀土+75%高岭土改性路基土路面铺装厚度和施工深度均最小,分别为30,80mm。道路工程建设过程中遇到膨胀土路基时,优先采用化学稳定剂进行处理而非拆除更换,并在施工过程中密切监控路基土关键指标,特别是在多雨地区加强排水设计,确保道路的长期稳定性和耐久性。This study conducts research on the optimization of pavement thickness and construction depth of modified subgrade soil based on the California bearing ratio(CBR).Three types of subgrade soils with different quality ratios were prepared,which are 25%expansive soil+75%kaolin,35%expansive soil+65%kaolin,75%expansive soil+25%kaolin,and chemically treated with a mixture of 20%cement and 8%lime.The engineering properties of the subgrade soil were studied through Atterberg limit tests,Proctor compaction tests,California bearing ratio tests,and expansion tests.The research results show that the liquid limit,plastic limit,plasticity index,moisture content and expansion rate of unmodified subgrade soil all increase with the increase of expansive soil content.The California bearing ratio of unmodified subgrade soil does not meet the specification requirements,while that of modified subgrade soil significantly increases,meeting the requirements of road construction.The modified subgrade soil reduces the pavement thickness and construction depth,with the mixture of 25%expansive soil+75%kaolin having the smallest pavement thickness and construction depth,both at 30mm and 80mm respectively.In road construction,when encountering expansive soil subgrade,it is preferred to use chemical stabilizers for treatment rather than removal and replacement.During construction,closely monitor key indicators of subgrade soil,especially in rainy areas,strengthen drainage design to ensure the long-term stability and durability of the road.

关 键 词：道路 路基 承载比 膨胀率 铺装厚度 施工深度 

分 类 号：TU997[建筑科学—市政工程]