软土地基桥台稳定控制及现场才监测技术研究-岩土工程专业毕业论文.docx

摘要对于修建在深厚软土地基上的桥台，如果台后路基填土较高，桥 摘要 对于修建在深厚软土地基上的桥台，如果台后路基填土较高，桥 头下卧软土层将在上覆路堤荷载作用下产生侧向塑流和固结，若处理 不当，会对桥台稳定产生非常不利的影响，如使桥跨距减小，无法架 梁，甚至在施工或运营中使桥台严重变形、桩基折断等。 本文对位于深厚软土地基上的温福铁路对务山特大桥温州桥台 在施工阶段进行现场监测，并且结合理论分析，进行了高填路堤下深 层软土地区桥台稳定性研究： (1)根据国内外文献资料，总结了目前桥头路基填筑对软基桥台 稳定影响的现场试验、室内试验和数值计算等诸多研究方面已经取得 的成果。 (2)分析了软土地基桥台台后路基填筑对桥台稳定的影响，探讨 了台后路基填土引起软土变形对桥台桩产生的侧向压力和负摩阻力 的计算方法，并对这些计算方法进行分析比较。 (3)分析了软土地基桥台病害的原因及表现形式，归纳了软土地 基桥台稳定的关键影响因素，总结了软土地基桥台的稳定控制措施。 (4)开展了对务山特大桥温州桥台施工阶段监测，整理和分析了 已经取得的初步监测成果。 (5)采用大型通用有限元软件ADINA对在台后路基堆载作用下软 基桥台桩基的性状进行三维分析，获得了桩基受台后路基填筑影响的 变形规律。 关键词：软土地基，桥台，稳定控制，现场监测，有限元法 ABSTRACTⅥmen ABSTRACT Ⅵmen the abutment iS built 011 deep soft ground．soft soil’horizontal movement and consolidation will take place under the pressure of the high embankment behind the abutment，which can weaken the abutment stabilization and bing it various diseases if effective measures fa订to be taken，such as the girder call be not fixed，the abutment deform badly,and piles are broken in the course of construction and management． Based on monitoring the臃nzhou Abutment of the Duiwushan Bridge of Wenzhou-Fuzhou Railway dudng its constructing，the paper carrys through the research on stabilization of the abutment on deep soft ground and under hi曲embankment as follows： (1)According to relational literatures，the current research situation of embankment lateral effects on the piled bridge abutment on soft clay iS analyzed．The field monitoring results and centrifuge model tests of the piled bridge abutment on soft ground，finite element analysis of the soil．pile interaction and various computation techniques of the lateral earth pressure acting on the piles from horizontal soil movements are summarized． (2)The aspects of the hi曲-filling embankment action for the abutment stabilization are summarized，the methods of the additional horizontal soil pressure and the negative friction on the abutment piles are discussed and compared． (3)The causes and forms of the abutment diseases are analysed，the key effect fact