单箱双室简支箱梁的剪力滞效应研究

发布时间：2019-07-01 17:23

【摘要】：研究目的:多室箱梁在竖向弯曲变形时,对应于初等梁理论纵向应力计算模式,存在多种横向剪力滞效应模式。本文在分析单箱双室箱梁剪力滞效应的基本模式和力学机理的基础上,结合铁路单箱双室简支箱梁算例,研究在跨中集中力和满跨均布荷载下,不同剪力滞效应模式的分布规律。以对剪力滞效应影响较为突出的高跨比为变量,研究高跨比变化对各剪力滞模式的影响规律。研究结论:通过对双室箱梁的剪力滞效应分析,得出:(1)以双室箱梁为代表的多室箱梁,对应于同一纵向对称荷载,存在着多种剪力滞效应模式,且不同模式的剪力滞效应差异较大;(2)在单箱双室箱梁的多种剪力滞效应模式中,集中力仅作用于中腹板时,截面的剪力滞效应最为突出,同时剪力滞效应对高跨比的改变最为敏感;(3)考虑到多室箱梁剪力滞效应的多模式性,在进行多室箱梁设计时,应充分考虑不同荷载作用模式对剪力滞效应的影响;(4)本文研究方法和结论可为多室箱梁桥的设计和力学分析提供理论借鉴。
[Abstract]:Research purpose: when multi-chamber box girder is deformed in vertical bending, it corresponds to the theoretical longitudinal stress calculation model of primary beam, and there are many kinds of transverse shear lag effect models. Based on the analysis of the basic model and mechanical mechanism of shear lag effect of single box and double chamber box girder, combined with an example of railway single box double chamber simply supported box girder, the distribution law of different shear lag effect modes under concentrated force in the middle span and uniform load with full span is studied in this paper. Taking the high-span ratio, which has a prominent influence on the shear lag effect, as a variable, the influence of the change of the high-span ratio on each shear lag model is studied. Research conclusion: through the analysis of shear lag effect of double-chamber box girder, it is concluded that: (1) the multi-chamber box girder represented by double-chamber box girder has many shear lag effect modes corresponding to the same longitudinal symmetrical load, and the shear lag effect of different modes is quite different; (2) among the various shear lag effect modes of single box and double chamber box girder, the shear lag effect of section is the most prominent when the concentrated force only acts on the middle web, and the shear lag effect is the most sensitive to the change of high span ratio. (3) considering the multimode of shear lag effect of multi-chamber box girder, the influence of different load action modes on shear lag effect should be fully considered in the design of multi-chamber box girder. (4) the research method and conclusion of this paper can provide theoretical reference for the design and mechanical analysis of multi-chamber box girder bridge.
【作者单位】：兰州交通大学;
【基金】：国家自然科学基金(51168030,51208242,51368031) 教育部“长江学者和创新团队发展计划”(IRT1139) 甘肃省杰出青年基金(1210RJDA009) 中国博士后科学基金(2012M521815)
【分类号】：U441.5

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