弯曲荷载下钢—混组合梁腹板稳定性试验研究

发布时间：2018-01-05 19:20

本文关键词：弯曲荷载下钢—混组合梁腹板稳定性试验研究　出处：《武汉理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：钢-混组合梁桥不仅具有受力性能良好、较好的抗震性能、自重轻、施工方便等优点,较大的跨越能力是钢-混组合梁桥另一显著优点。当对桥梁跨径需求较大时,钢-混组合梁桥是优先考虑的桥梁结构形式。随着钢-混组合梁桥跨径的增大,钢-混组合梁桥的腹板高度也随之增加,一般的大跨径钢-混组合梁桥的高跨比为1/20~1/25。钢-混组合梁桥中腹板高度的增加,对钢-混组合梁桥的设计提出了新的挑战,我国现有的桥梁设计规范在一定程度上并不能满足钢-混组合梁桥腹板的设计与验算要求。钢-混组合梁桥中腹板的稳定性问题归根结底还是板件稳定性问题,而板件边界条件的确定是进行板件稳定性问题研究分析的关键,目前板件稳定性分析理论对板件的边界条件主要采用两种简化形式:四边简支边界与四边嵌固边界。钢-混组合梁桥中,混凝土桥面板与钢主梁之间主要是通过剪力钉进行连接。混凝土桥面板、剪力钉、钢主梁翼缘对腹板均会产生弹性转动约束作用,钢-混组合梁桥钢腹板边界具有明显的弹性转动约束特征,实际边界是介于简支边界与嵌固边界之间。本人所在课题组研究了剪力钉布置方式、结构尺寸、材料参数等影响因素对组合翼缘弹性转动约束系数χ的影响,并推导了考虑剪力钉布置方式、结构尺寸、材料参数等影响因素的组合翼缘弹性转动约束系数χ的计算公式及钢-混组合梁腹板临界屈曲应力计算公式,开展了剪切荷载下钢-混组合梁的腹板屈曲试验研究工作,采用试验手段验证了剪切荷载下上述公式的适用性与正确性。本文在以上研究基础上完成了弯曲荷载下钢-混组合梁腹板稳定性试验研究工作,主要完成工作如下:(1)分析国内外关于板件稳定性的研究现状。通过查阅大量国内外文献,对国内外关于板件稳定性的研究现状进行深入了解,分析现有研究存在的不足之处,说明开展弯曲荷载下钢-混组合梁腹板稳定性试验研究的重要意义,在本人所属课题组之前关于钢-混组合梁腹板稳定性的研究基础上针对这些不足引出本文的研究主要内容与拟解决的关键科学问题。(2)介绍钢-混组合梁腹板弯曲屈曲分析理论。详细介绍了考虑剪力钉布置方式、结构尺寸、材料参数等影响因素的组合翼缘弹性转动约束系数χ的计算公式,在此基础上介绍了弹性转动约束边界的钢-混组合梁腹板弯曲临界屈曲应力的计算公式,为后续开展弯曲荷载下钢-混组合梁腹板稳定性试验研究奠定理论基础。(3)钢-混组合梁腹板弯曲屈曲有限元数值分析。采用有限元数值分析方法,运用ANSYS软件对钢-混组合模型试验梁进行建模,对两点集中荷载下有限元模型的屈曲特性进行了分析。获得了试验梁有限元模型的跨中竖向位移、腹板平面外位移、应力分布、屈曲模态等有限元分析结果。通过有限元分析结果与本文公式计算结果的对比,验证本文计算公式的正确性。(4)钢-混组合梁腹板弯曲屈曲试验研究。采用试验手段,对弯曲应力作用下钢-混组合模型试验梁的弯曲屈曲特性开展了研究。通过试验结果与本文公式计算结果的对比,对本文弯曲临界屈曲应力计算公式的正确性进行验证。试验还研究了剪力钉布置方式对组合翼缘弹性转动约束系数χ与腹板弯曲临界屈曲应力的影响规律,获得了弯曲应力作用下不同剪力钉布置方式的钢-混组合模型试验梁的屈曲模态与弯曲临界屈曲应力试验结果。
[Abstract]:The steel-concrete composite beam bridge not only has good mechanical performance, good seismic performance, light weight, the advantages of convenient construction, large span steel concrete composite beam bridge is another significant advantage. When the large span of demand, the steel-concrete composite beam bridge is a bridge structure form is preferred. With the increase of the steel-concrete composite beam bridge, steel-concrete composite beam bridge web height increases, large span steel concrete composite beam bridge general high span ratio is the combination of increased web height of beam bridge of steel mixed 1/20~1/25., steel-concrete composite beam bridge design new the challenge of our country, the existing bridge design specifications do not meet in a certain extent - Requirements for design and calculation of mixed steel composite beam bridge web. The steel-concrete combined girder bridge stability problem after all in the web or sheet and plate to determine the stability of boundary condition is The key problem of the stability analysis of plate, the plate boundary conditions on the stability analysis theory of plate mainly adopts two kinds of simplified forms: simplysupported boundary and fixed boundary edges. The steel-concrete composite beam bridge, between concrete deck and steel girder is mainly through shear nail concrete bridge connection. The panel, shear studs, steel girder flange on the web will produce elastic rotation restraint, steel-concrete composite beam bridge steel webs boundary has obvious elastic constraint characteristics, the actual boundary is between simply supported boundary and fixed boundary. In my research group of the shear studs arrangement, structure size, influence the factors of material parameters influence on flange elastic constraint coefficient Chi, and considering the shear stud layout, structure size, material parameters, effect of combined flange elasticity factors about beam rotation coefficient Beam web buckling stress calculation formula of mixed formula X and steel, the composite beam plate buckling test on mixed shear steel, the test means to verify the applicability and validity of the formula of the shear load. Based on the above research foundation completed the beam web experimental study on stability of mixed steel under bending load, the main work is as follows: (1) analysis on the plate stability research status at home and abroad. Through consulting a large number of domestic and foreign literature, research status on the plate stability at home and abroad to further understand, analysis of deficiencies existing in the current research, that carry out bending load under the steel and concrete significance test on stability of beam webs, in my own research group before basic research on steel-concrete composite girder stability. To solve these problems lead to the The main contents of this paper and the key scientific issues. (2) the concrete composite beam web bending buckling analysis theory of steel was introduced in detail. The shear pin arrangement, structure size, combination of flange elastic factor rotation constraint coefficient Chi calculation formula of material parameters and other factors, on the basis of introduced constraints the boundary elastic rotation of steel-concrete composite beam plate bending calculation formula of critical buckling stress, for further lay a theoretical foundation for experimental study on stability of beam web mix under bending load of steel. (3) steel-concrete composite girder bending buckling finite element numerical analysis using the finite element numerical analysis method, the use of ANSYS the software of the steel-concrete combined beam model test model for two concentrated buckling characteristic finite element model under load is analyzed. The vertical displacement of mid span beam finite element model test, abdominal plate Out of plane displacement, stress distribution, buckling finite element analysis results. Comparing the calculated results with the formula in this paper through the finite element analysis results, the correctness of the calculation formula is verified in this paper. (4) experimental study on the flexural buckling of the beam web. The mixed combination of steel - Test method of bending stress under the action of steel concrete the bending buckling characteristics of test beam combination model was studied. The formula by comparing the calculated results with the test results, to verify the correctness of this bending critical buckling stress formula. Influence of experimental research of shear stud arrangement on the combination of flange and web x elastic rotation restraint coefficient of bending critical buckling stress the obtained bending stress under different shear stud buckling mode arrangement of steel-concrete combined beam model test and bending buckling stress test results.

【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U446

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