高速公路软土路基加宽处治关键技术研究

发布时间：2018-07-25 18:53

【摘要】：随着当前交通量的迅速增长,高速公路面临着扩建加宽的问题,尤其是对于软土地基段高速公路的加宽需要进行更为复杂的分析与处理。现有高速公路的加宽没有成熟的经验可循,并且从设计到施工存在很多约束条件;另外,已完成的加宽工程中存在着一些技术问题,工程效果不能得到保证。因而对软基高速公路加宽进行系统研究十分迫切。首先,本文分析了高速公路加宽后产生的病害与处置技术。列出了一些主要的病害并从理论上分析了病害产生的原因,以及一些处理路基病害的技术方法。然后,通过对施工段k79的工况分析,包括CFG桩与旋喷桩两种方式,通过施工与计算得到提高承载力的方法,并用数值模拟,描绘出沉降曲线图,分析关于地基沉降的问题,比较两种桩处理方式的优劣,对未来施工提出合理的建议。最后,通过实验的方法对老路基边坡的状态进行了调查,包括了多个角度:沿横断面的分布、沿高度的分布、堤身状态分析、边坡台阶开挖试验、搭接处补强技术等。同时看出大部分老路堤边坡土体的压实度达不到设计要求,因此采用强力夯实机追密技术对边坡新老路基搭接部位进行补强,并利用液态粉煤灰回填技术解决桥头跳车、台背回填沉降等问题。
[Abstract]:With the rapid growth of traffic volume, the expressway is faced with the problem of expansion and widening, especially for the soft soil section of the highway widening needs to be more complex analysis and treatment. There is no mature experience in the widening of the existing freeway, and there are many constraints from design to construction. In addition, there are some technical problems in the completed widening project, and the engineering effect can not be guaranteed. Therefore, it is very urgent to study the widening of soft-foundation expressway systematically. First of all, this paper analyzes the disease and disposal technology after highway widening. Some main diseases are listed and the causes of these diseases are analyzed theoretically, as well as some technical methods to deal with subgrade diseases. Then, through the analysis of the working conditions of K79 in the construction section, including CFG pile and rotary jet pile, the method of improving the bearing capacity is obtained by construction and calculation, and the settlement curve is described by numerical simulation, and the problems about foundation settlement are analyzed. The advantages and disadvantages of the two kinds of pile treatment are compared, and reasonable suggestions for future construction are put forward. Finally, the state of the old roadbed slope is investigated by the experimental method, including the distribution along the cross section, the distribution along the height, the analysis of the state of the embankment, the excavation test of the slope step, the reinforcement technology at the lap joint and so on. At the same time, it can be seen that the compaction degree of most of the old embankment slope soil can not meet the design requirements, so the new and old embankment overlapped parts of the slope are reinforced by using the strong compaction machine and the liquid fly ash backfill technology is used to solve the bridge-head jump. Backfill settlement of abutment and so on.
【学位授予单位】：石家庄铁道大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U416.1

【参考文献】