带加劲肋钢-混凝土组合蜂窝梁开孔腹板的抗剪性能

发布时间：2018-03-19 23:26

本文选题：桥梁工程　切入点：抗剪承载力　出处：《公路交通科技》2017年08期 　论文类型：期刊论文

【摘要】：带加劲肋钢-混凝土组合蜂窝梁腹板成排开孔后,主要削弱了其抗剪稳定性和抗剪强度。为探明这一新型桥梁结构的力学特点,采用有限元方法对钢-混凝土组合蜂窝梁开孔腹板的抗剪性能进行了深入研究。对不同边界条件下的开孔腹板进行弹性剪切屈曲分析,考虑孔洞的影响引入径高比和宽高比参数,对实腹板剪切屈曲系数加以修正,并引入约束系数表征约束程度,推导得到了开孔腹板剪切屈曲系数的计算公式。建立开孔腹板抗剪极限承载能力有限元计算模型,考虑材料、几何双重非线性,对不同参数开孔腹板的抗剪承载能力进行了大量的有限元分析,在数据分析基础上量化弹性屈曲荷载和屈曲后荷载对开孔腹板抗剪承载能力的贡献。引入腹板的开孔率参数,提出了开孔腹板抗剪极限承载力的计算公式,同时分析了不同初始几何缺陷对开孔腹板抗剪性能的影响。结果表明:不同边界条件下的开孔腹板剪切屈曲系数公式与有限元值吻合良好;开孔腹板仍可发展一部分屈曲后强度,屈曲后强度可偏保守地表示为开孔腹板塑性强度的30%,开孔腹板抗剪极限承载力计算公式与有限元计算结果吻合较好,且总体偏于安全;不同的初始几何缺陷对开孔腹板荷载-位移曲线形式有较大影响,但对其抗剪承载能力影响很小。
[Abstract]:The steel-concrete composite beehive beams with stiffened ribbed beams are subjected to a row of openings, which weaken the shear stability and shear strength of this new type of bridge, so as to find out the mechanical characteristics of this new type of bridge structure. The shear behavior of the perforated web plate of steel-concrete composite honeycomb beam is studied by finite element method. The elastic shear buckling analysis of the perforated web plate under different boundary conditions is carried out. Considering the influence of the hole, the ratio of diameter to height and the ratio of width to height are introduced to modify the shear buckling coefficient of the real web, and the constraint coefficient is introduced to characterize the degree of constraint. The calculation formula of shear buckling coefficient of open web is derived. The finite element model of ultimate shear capacity of open web is established. The material is considered and the geometry is doubly nonlinear. Based on the finite element analysis of the shear bearing capacity of the web with different parameters, the contribution of the elastic buckling load and the post-buckling load to the shear bearing capacity of the open web is quantified on the basis of the data analysis, and the opening rate parameter of the web is introduced. A formula for calculating the ultimate shear capacity of a web with an open hole is presented. At the same time, the effects of different initial geometric defects on the shear resistance of the open web are analyzed. The results show that the formula of shear buckling coefficient of the open web under different boundary conditions is in good agreement with the finite element value. A part of post-buckling strength can still be developed in the open-hole web, and the post-buckling strength can be expressed conservatively as 30 of the plastic strength of the open-hole web. The formula for calculating the ultimate shear capacity of the open-hole web is in good agreement with the finite element calculation results, and the overall deviation is safety. Different initial geometric defects have great influence on the load-displacement curve form of the open web, but have little effect on its shear bearing capacity.
【作者单位】：中南林业科技大学土木工程与力学学院;湖南大学土木工程学院;
【基金】：国家自然科学基金项目(51508581) 湖南省自然科学基金项目(2016JJ3188) 湖南省交通运输厅科技进步与创新项目(201527) 中南林业科技大学引进高层次人才科研启动基金项目(104/0333)
【分类号】：U441

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