To develop a methodology for evaluating fire resistance of high strength Q460 steel columns, the load bearing capacity of high strength Q460 steel columns is investigated. The current approach of evaluating load beari...To develop a methodology for evaluating fire resistance of high strength Q460 steel columns, the load bearing capacity of high strength Q460 steel columns is investigated. The current approach of evaluating load bearing capacity of mild steel columns at room temperature is extended to high strength Q460 steel columns with due consideration to high temperature properties of high strength Q460 steel. The critical temperature of high strength Q460 steel column is presented and compared with mild steel columns. The proposed approach was validated by comparing the predicted load capacity with that evaluated through finite element analysis and test results. In addition, parametric studies were carried out by employing the proposed approach to study the effect of residual stress and geometrical imperfections. Results from parametric studies show that, only for a long column （slenderness higher than 75）, the magnitude and distribution mode of residual stress have little influence on ultimate load bearing capacity of high strength Q460 steel columns, but the geometrical imperfections have significant influence on any columns. At a certain slenderness ratio, the stability factor first decreases and then increases with temperature rise.展开更多
以某500 k V工程为例,针对城区输电线路建设面临走廊、景观等诸多限制条件的问题,提出一种新型钢管杆的杆塔形式,从加工可行性、材质、结构布置、截面形状、试验等方面进行分析比较。所得结果表明:材质推荐Q460高强钢;直线杆采用双杆布...以某500 k V工程为例,针对城区输电线路建设面临走廊、景观等诸多限制条件的问题,提出一种新型钢管杆的杆塔形式,从加工可行性、材质、结构布置、截面形状、试验等方面进行分析比较。所得结果表明:材质推荐Q460高强钢;直线杆采用双杆布置,椭圆形截面;耐张杆采用四杆布置,正多边形截面;杆体及节点的强度和刚度均符合设计要求,并有一定的安全储备。新型钢管杆为市区输电线路提供了有效的解决方案。展开更多
基金The authors wish to acknowledge the support from the Funding Plan for Young Teachers in Universities of Chongqing, Natural Science Foundation of China （Grant No. 51008320）, China Postdoctoral Science Foundation （Grant No. 20110490811） and China Postdoctoral Science special Foundation （Grant No. 2012T50765）. Any opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of the sponsors.
文摘To develop a methodology for evaluating fire resistance of high strength Q460 steel columns, the load bearing capacity of high strength Q460 steel columns is investigated. The current approach of evaluating load bearing capacity of mild steel columns at room temperature is extended to high strength Q460 steel columns with due consideration to high temperature properties of high strength Q460 steel. The critical temperature of high strength Q460 steel column is presented and compared with mild steel columns. The proposed approach was validated by comparing the predicted load capacity with that evaluated through finite element analysis and test results. In addition, parametric studies were carried out by employing the proposed approach to study the effect of residual stress and geometrical imperfections. Results from parametric studies show that, only for a long column （slenderness higher than 75）, the magnitude and distribution mode of residual stress have little influence on ultimate load bearing capacity of high strength Q460 steel columns, but the geometrical imperfections have significant influence on any columns. At a certain slenderness ratio, the stability factor first decreases and then increases with temperature rise.
文摘以某500 k V工程为例,针对城区输电线路建设面临走廊、景观等诸多限制条件的问题,提出一种新型钢管杆的杆塔形式,从加工可行性、材质、结构布置、截面形状、试验等方面进行分析比较。所得结果表明:材质推荐Q460高强钢;直线杆采用双杆布置,椭圆形截面;耐张杆采用四杆布置,正多边形截面;杆体及节点的强度和刚度均符合设计要求,并有一定的安全储备。新型钢管杆为市区输电线路提供了有效的解决方案。
