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ID:32511027
大小:1.81 MB
页数:81页
时间:2019-02-10
《剪力滞对悬臂施工桥梁影响的研究》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、摘要现代桥梁施工中,经常采用薄壁箱形梁结构,然而,薄壁箔形梁在纵向弯曲时会产生剪力滞效应,忽略剪力滞效应的影响,将会造成结构设计的不安全。近年来,国内外学者对剪力滞现象进行了研究与探讨,取得了一些成果,但还存在着许多问题。本文首先详细阐述了薄壁箱形粱剪力滞后效应的概念以及剪力滞效应对结构的不利影响,总结了目前工程界解决剪力滞问题的各种研究理论和方法,评价了各种理沦和方法的适用性和局限性及以后的研究发展方向,并对研究现状进行了展望。针对以往假设的位移函数与实际情况并不符合,本文假设剪力滞纵向位移函数按m次抛物线分布,运用能量变分法推导出箱形梁在横向荷载作用下的微分方程,并
2、获得解析解。通过算例与ANSYS分析结果对比确定了较为符合的/'/l值。在悬臂梁中会产生负剪力滞现象,本文就负剪力滞现象进行了阐述,并结合具体算例分析了影响悬臂梁负剪力滞效应的因素。用有限元软件ANSYS模拟了连续梁桥悬臂旌工过程,计算了斜拉桥在自重及二期恒载作用下主梁的剪力滞效应,找到了悬臂旋工过程中的剪力滞分布情况,并将ANSYS和其他计算方法的结果作了对比,较为吻合。关键词:剪力滞,负剪力滞,能量变分法,悬臂旅工AbstraclAbstractThin.walledboxgirderisoftenusedinmodembridgeengineering..Howe
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