【作者】 曹现雷；

【导师】 郝际平；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2010， 博士

【摘要】 高强角钢以其优越的高强度性能、建造适应性及经济性而在输电线铁塔中得到了越来越广泛的应用。论文以热轧Q460高强单角钢在输电线路铁塔结构设计的应用为研究目的,结合输电铁塔主材角钢构件的三种连接形式,设计了48根轴心受压角钢构件、48根一端轴心一端偏心受压角钢构件和48根两端偏心受压角钢构件,对三类共计144根受压构件进行了静力加载试验研究。研究了不同截面型号、不同长细比和不同端部支座条件下高强角钢的破坏模式、极限承载力、变形性能和截面应变分布等力学性能特征。为深入理论分析和提出工程设计建议提供了基础的试验素材。试验表明,小长细比试件局部屈曲失稳起控制作用,大长细比试件整体失稳起控制作用。长细比越大,试验值越高于理论值,用现行规范设计高强角钢受压构件会越安全。宽厚比越大,对小长细比构件中载面扭转效应影响较大。轴心受压构件试验可采用双刀口支座代替球铰支座；一端轴心一端偏心受压试件轴心端可采用双口支座或球铰支座；两端偏心受压试件试验表明,美国ASCE10-1997导则公式中考虑了角钢构件端部有利约束效应。采用有限元分析软件ANSYS对试件进行三维实体建模,仿真分析时考虑材料非线性、几何非线性、接触非线性等因素影响。分析了构件的变形模态、极限承载能力、长细比对转角影响、宽厚比对承载力的影响及残余应力的影响等受力性能。有限元结果与试验结果吻合良好,残余应力对试件承载力影响小于5%。在模型试验和仿真试验的基础上提出了新的稳定系数曲线模型,依据稳定系数公式建立相应的设计方法,结合参数分析给出了设计Q460高强角钢受压构件稳定承载力的实用计算公式。将试验结果和本文建议公式计算结果进行了比较,结果表明,建议公式与试验结果吻合较好。论文对Q460角钢受压构件的试验和理论分析结果可供工程设计或相关研究参考。更多还原

【Abstract】 High-strength angle steel has been widely used in transmission towers because of their excellent high yield strength, constructional suitability and economy. To study the application of Q460 high-strength hot-rolled equal-leg single-angle in the design of transmission tower, according to three kinds of connection forms about leg members in transmission tower, design-ed 48 single-angle axial compression members,48 single-angle compression members with a concentric load at one end and normal framing eccentricity at the other end, and 48 single-angle compression members attached by one leg. A total of 144 compression members were tested under static loading to investigate failure process, bearing capacity, deformation performance and strain distribution of high-strength angle steel when having with different section types, different slenderness ratios and different end supports. For further theoretical analysis and engineering design proposals provide the basis test material.The experiment result showed most of the small slenderness members were controlled by local buckling, and the large ones were controlled by overall buckling. The greater the slenderness ratio, the higher the test value than the theoretical value, using the existing standard design high-strength angle compression members will be more secure. The larger width-thickness ratios, the greater impact to torsion effect of middle section of the small slenderness members. Axial compression test can use double knife-edge bearing to instead spherical hinge bearing; for the single-angle with an eccentric load at one end and normal framing eccentricity at the other end, the axial laod end can use double knife-edge bearing or spherical hinge beraing; for single-angle steel struts connected by one leg, the experiment result shows’Guide for design of transmission tower’(ASCE10-1997) by American Society of Civil Engineers considered favorable constraint effort at end of members. Comprehensive three-dimensional finite element models were presented for test specimens using the ANSYS11.0 nonlinear finite element program. The material nonlinearity, geometric nonlinearity and contact nonlinearity were considered when simulation analysis. The deformation modes, the ultimate bearing capacity, the influence of slenderness on torsion angle, the influence of width-thickness ratio on bearing capacity and the influence of residual stress were investigated. FEM results were agree well with the experimental results, The residual stesses affected the ultimate load-carring capacity by about 5%.The new stability factor curve models were proposed based on experimental study and simulation analysis, according to the formula of stability factor to establish appropriate design method. By parameter analysis, the stability capacity practical formula on designing Q460 high-strength angle steel compression members. Comparison between the proposed formulas and experimental data demonstrated that they can accurately predict the stability capacity of compression members, which showed these methods are feasible.These experimental and theoretical results about Q460 high-strength angle compression members can guide engineering design or research reference.更多还原