【作者】 郑伟；

【导师】 洪宝宁；

【作者基本信息】 河海大学 ， 岩土工程， 2005， 硕士

【摘要】 本文针对在实际工程中,可能出现施工工序不当(先打桩后软基处理)和营运期桥头过渡段再处理情况,从减少桥桩的水平位移、保证后续施工,以及再处理过程中桥梁的安全等问题出发,通过理论分析、数值计算和工程实例解析,提出用力法结合弹性梁理论的分析方法;结合实际工程,对软基处理和路堤填筑对邻近桩的影响进行系统研究:根据现阶段存在的不足和亟特解决的问题,提出了一些合理的建议和防范措施。具体研究内容如下: 1)在不同软基处理形式下,根据实际情况模拟并依据实际工况进行简化处理,以研究在软基处理过程中,施工和路堤填筑对桩的影响。 2)将桩体和土体作为整体来考虑软基处理和路堤填筑作用下桩体受土体水平位移的变形性状,提出路堤填筑过程中,影响桩体水平侧移的计算模型。 3)作为计算模型的理论分析,讨论了软基未处理情况下,路堤填筑对地基土体水平位移的影响,提出影响因素并对这些影响因素进行数值计算,得出桩身侧向的变形规律。根据桩身侧向变形的计算结果,提出合理的地基处理方案,并对加固后的效果进行计算分析。 4)依据工程实例,选取计算模型参数和理论分析方法,利用自己编制的计算程序,进行数值计算,并将计算结果与常规有限元数值计算结果进行比较与分析,验证研究方法的正确性。 5)在大量阅读和总结国内外有关被动桩及过渡段软土地基研究资料的基础上,针对先成桩、后处理再进行路堤填筑的问题,从软基处理和路堤填筑对邻近桥桩作用的机理、作用特点和现场测试结果出发,进行理论分析、数值计算和工程实例解析。更多还原

【Abstract】 This thesis put forward a mathematical analysis using force method with the theory of beam on elastic foundation through theoretical analyzing , numerical calculation and analytical case. It started with the problems on decreasing the horizontal displacement of the pile , assuring the subsequent handling, danger of bridge and so on by aimed at the case of the unconscionable construction sequences in the construction and the reprocessing at the bridge’s transition during the working . The thesis does the system research on the impact that the soft soil improvement and embankment reclaiming acts on adjacent piles ; According to some shortcoming and problem which need to be dealt with urgently in recently phase, some sound advice and countermeasures are brought forward. The detailed contents are as follows:1, In order to study the impact that soft soil improvement and embankment reclaiming acts on the adjacent piles, the mode is established in varied soft soil improvement form in response to practical situation.2, The calculation mode is put forward which impacts the horizontal displacement of adjacent piles in the process of improving soft foundation and embankment reclaiming, in which soil mass and adjacent pile shaft are whole mass.3, As a mode of theoretical analyzing, some impacts that embankment reclaiming acts on piles are discussed in the untreated soft foundation, and some influencing factors that act on adjacent piles are put forward and analyzed; and some deforming rules are gained in the pile shaft. According to results of deforming rules, some soft foundation disposing program is brought forward, and reinforcement effect is analyzed.4, According to case history, selective parameters of calculation mode and methods of theoretical analytic, using the program that is compiled to do numerical calculation, and proving that research technique is correct or not through comparison and analysis of the results to measured data and results of F.E.M.5, After abundant research data be read and summarized that is about passive pile and soft foundation processing mode in the bridge transition, aiming at those problems such as the unconscionable construction sequences, and from the mechanics that soft foundation disposing and embankment reclaiming act on adjacent pile, the characteristic of action, and test result in the field engineering, the theoretical analysis, numerical calculation and analytic case history is done.更多还原