南方湿热地区典型路基土干法与湿法击实试验对比研究

发布时间：2018-06-14 23:36

本文选题：路基土 + 击实　；参考：《长沙理工大学》2014年硕士论文

【摘要】：路基作为路面结构的基础,不仅承受着自身填土的重力和上覆路面结构带来的重力,还需要承受路面上部传递下来的行车荷载。一直以来,道路工程研究中存在着“重路面,轻路基”的现象,导致路基建造技术等相关领域的研究相对滞后。路基施工过程中路基土的含水率对路基填筑质量影响很大,处理不当易导致后期的路面结构产生不均匀沉降、车辙、开裂等病害,严重影响道路的路用性能和使用寿命。我国南方湿热地区路基土湿度较大,研究南方湿热地区高速公路典型路基土的干法、湿法击实试验差异性及寻找不同路基土对应于各自合理的施工含水率对指导路基路面设计具有重要意义。本文以在建的南昌至樟树高速公路改扩建工程为依托,针对南方湿热地区的典型路基土,系统展开了路基土的室内外试验研究。本文的主要研究内容一共分为两块：第一,探讨南方湿热气候条件下不同种类的典型路基土干法、湿法击实试验的最佳含水率之间的关系,可为今后公路工程路基施工提供更多更可靠的依据和规律。在昌樟高速改扩建路段选取典型的三种类型土样：一般黏土、高液限土、砂性土,分别进行了土的筛分试验、液塑限试验、干法、湿法击实试验,分析了试样的基本土质特征和工程特性,得到了三种南方典型高速公路路基土的干法、湿法击实试验对应最佳含水率之间的关系。第二,依据击实试验获得的最佳含水率,按2%～3%的含水率递增(减),进行路基土的强度(CBR)试验研究,得到相应路基土的CBR值,评价了路基土的路用性能。在此基础之上,提出了南方湿热地区三种典型路基土在满足工程要求前提下,路堤施工对应的含水率范围,并结合试验,分析了不同种类土的最佳含水率与CBR强度值之间存在的关系。本文通过对南方高速公路三种典型路基土的相关研究,具有以下创新点：通过试验结果分析,总结并得出了三种土干法、湿法击实试验最佳含水率间的关系,以及满足工程要求的施工含水率范围。研究成果对南方地区典型路基土填筑路堤具有指导意义。
[Abstract]:As the foundation of pavement structure, subgrade not only bears the gravity of its own fill and overlying pavement structure, but also needs to bear the traffic load transferred from the upper part of the pavement. The phenomenon of "heavy road surface, light roadbed" has been existed in road engineering research all the time, which leads to the relative lag of research on subgrade construction technology and other related fields. In the process of subgrade construction, the moisture content of subgrade soil has a great influence on the quality of subgrade filling, and improper treatment will lead to uneven settlement, rutting, cracking and other diseases of the pavement structure in the later stage, which seriously affects the road performance and service life of the road. The dry method of typical subgrade soil in south China is studied in this paper. The difference of wet compaction test and the search for different subgrade soil corresponding to their respective reasonable construction moisture content are of great significance to guide the design of subgrade and pavement. Based on the reconstruction and extension project of Nanchang-Zhangshu Expressway under construction, the indoor and outdoor test of subgrade soil is carried out systematically in this paper, aiming at typical subgrade soil in southern humid and hot area. The main contents of this paper are divided into two parts: first, the relationship between the optimum moisture content of different types of typical subgrade soil dry method and wet compaction test is discussed. It can provide more reliable basis and rule for roadbed construction of highway engineering in the future. Three typical types of soil samples were selected in Changzhang high-speed reconstruction and extension section: general clay, high liquid limit soil and sandy soil. Soil screening test, liquid-plastic limit test, dry method and wet compaction test were carried out respectively. The basic soil properties and engineering characteristics of the samples are analyzed, and the relationship between the wet compaction test and the optimum moisture content of three typical subgrade soils in the south of China is obtained. Secondly, according to the optimum moisture content obtained by compaction test, the CBR value of subgrade soil is obtained by increasing the moisture content of 2% and 3%, and the road performance of roadbed soil is evaluated. On this basis, three typical subgrade soils in southern humid and hot areas are put forward, and the corresponding water content range of embankment construction under the premise of meeting the engineering requirements is put forward, and combined with the test, The relationship between the optimum moisture content of different soils and the CBR strength is analyzed. Through the research on three typical subgrade soils of Nanfang Expressway, this paper has the following innovations: through the analysis of the test results, the relationship between the optimum moisture content of the three kinds of soil dry method and wet compaction test is summarized and obtained. And the scope of construction moisture content to meet the engineering requirements. The research results are of guiding significance for embankment filling with typical subgrade soil in southern China.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U416.1

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