文本描述
本科生毕业论文(设计)
题 目 :基于flac3D深基坑开挖模拟与支护设计
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摘 要
随着城市化过程中不断涌现的高层建筑和超高层建筑以及城市地下空间的开发,深基坑工程越来越多,深基坑工程项目的规模和复杂性日益增大,给深基坑工程的设计和施工带来了更大的挑战。在这样的背景下,深基坑支护结构设计和变形量预测已成为岩土工程领域的重要研究课题之一。本文以武汉市万达广场深基坑工程作为研究对象,利用勘查欧亿·体育(中国)有限公司和深基坑支护结构设计要求,比选合理的基坑支护方案并进行相应的计算设计。同时,本文针对深基坑工程变形量验算等难以解决的问题引用了flac3D数值模拟方法,对基坑开挖、支护结构施工进行全方位的模拟监测,将计算设计结果和模拟计算结果进行对比验算,得出比较合理的支护结构设计方案和变形量控制方案。
根据基坑实际情况和勘查欧亿·体育(中国)有限公司,本文选择的围护方案为以大直径混凝土排桩、双排桩、角撑与对顶撑相结合的内支撑为主的多种联合支护方案,结合坡顶大面积卸土减载、坑内被动区加固的措施。计算部分主要设计计算大直径混凝土排桩(钻孔灌注桩)桩长、内力和配筋,而对卸土减载、内支撑结构、坑内被动区加固和降水设计只进行了简要的说明;flac3D模拟部分主要从建立模型、设置大直径混凝土排桩、放坡开挖、放坡坡面土钉施工、预应力锚索(代替内支撑)施工和基坑主体开挖为顺序进行建模计算,最后进行变形量监测、分析,输出桩单元、锚单元的内力分布情况并给出相应的结论与建议。
本文以常规计算和数值模拟相结合的方式进行参考对比,常规计算和数值模拟分析结果非常接近,给出了有效合理的安全系数。
关键词:深基坑 支护设计 flac3D模拟 数值模拟
Abstract
With the urbanization process ,high-rise buildings and supertall buildings are continuously emerging .As a result ,underground space development project and deep excavation project become more and more. At the same time, the scale and complexity of deep excavation increasing bigger. they make the design and construction of deep excavation to face greater challenges. So structural design and deformation prediction of deep excavation has become an important research issue in the field of geotechnical engineering. In this paper, the deep excavation of Wanda Plaza, Wuhan is studied. And using survey data and structural design of deep excavation requirements to select reasonable foundation pit ,then to conduct the corresponding design. The meantime, as checking the deformation of deep excavation is a difficult problems ,it uses flac3D numerical simulation method to monitor the progress of deep pit’s excavation, construction .Then comparing the design results of the calculation and simulation results to obtained reasonable support structure design and control program of deformation. According to the actual situation and exploration data, the envelope of large diameter piles concr