%0 Journal Article
%T 斜拉桥桥塔节段力学性能<br>Mechanical property of segmental tower of cable-stayed bridge
%A 陈康明
%A 吴庆雄
%A 黄汉辉
%J 交通运输工程学报
%D 2016
%X 基于宁波市外滩大桥桥塔节段,采用预应力钢绞线自平衡加载方式进行1:3.34桥塔节段缩尺模型荷载试验,采用非线性有限元方法,研究了考虑初始缺陷和局部屈曲的桥塔节段的传力路径、受力特性、实际承载能力和局部失稳机理。研究结果表明:外荷载主要由主塔两外箱各板件承担,从靠近截面突变处开始,外箱和内箱各板的应力分别呈现递增和递减的趋势,内箱承受的外荷载逐渐向外箱传递,各板应力最大值均出现在截面形状突变处; 根据截面平均应力与测点应力的关系可将桥塔节段测点分成轴压、向钢箱内、外侧压弯三类; 试验得到桥塔节段的强度折减系数大于0.90,且采用有限元分析得到节段模型的极限荷载是理论极限荷载的1.06倍; 虽然纵向加劲肋和横隔板结构能有效防止桥塔结构中加劲板件的局部屈曲,但因截面突变处容易造成应力集中,是最易发生局部屈曲破坏的位置,因此,应注意截面突变处外箱顶底板与内腹板交接附近的纵向加劲肋的设计与施工; 在极限荷载作用下,外箱各板件在截面突变处会因局部屈曲而导致无法继续承载。<br>Based on the segmental tower of Waitan Bridge in Ningbo City, the axial compressive loading experiment of 1:3.34 scaled-model was conducted by using the prestressed steel strand self-balanced loading mode, and the force transferring route, mechanical characteristics, actual bearing capacity and local instability mechanism of segmental tower for cable-stayed bridge were studied by using finite element method and considering initial imperfections and local buckling. Analysis result shows that the external loads are mainly carried by the plates of two outer boxes, the stresses of the plates of outer and inner box increase and decrease from the sections closing to the abrupt changing section, the external load of inner box gradually transmits to outer box, and the maximum stresses of stiffened plates appear on the abrupt changing sections. The measurement points can be categorized into three kinds according to the relationship between the measured and sectional average stresses, including the points under axial compression and compression-flexure along the insider and outsider of steel box. The strength reduction coefficient of segmental tower is larger than 0.90 from the reduced-scale model experiment, and the ultimate bearing capacity of the model obtained by the finite element analysis is 1.06 times of theoretical ultimate bearing capacity. Although the local buckling of stiffened plates can be prevented effectively by using longitudinal stiffeners and diaphragms, the attention should be paid to the design and construction of longitudinal stiffeners near the intersection of top plates, bottom plates and inner web plates of two side boxes, especially the longitudinal stiffeners close to the abrupt changing section, since the abrupt changing section easily leads to the stress concentration, and it is likely to occur local buckling. The stiffened plates of outsider of steel box for the segment model fail to resist larger applied loads due to the local buckling occurring on the abrupt changing section. 2 tabs, 38 figs, 26 refs
%K 桥梁工程
%K 斜拉桥主塔
%K 缩尺模型试验
%K 非线性有限元
%K 强度折减系数
%K 局部屈曲&lt
%K br&gt
%K bridge engineering
%K main tower of cable-stayed bridge
%K reducing scale-model experiment
%K nonlinear finite element
%K strength reduction coefficient
%K local buckling
%U http://transport.chd.edu.cn/oa/DArticle.aspx?type=view&id=201605003