高强螺栓缺失对整体节点疲劳性能影响研究

Study on the Influence of High Strength Bolt Missing on the Fatigue Performance of Integral Joints

以湖北白洋长江大桥为工程背景,研究高强螺栓缺失对整体节点疲劳性能的影响。使用Ansys Workbench建立整体节点有限元模型,基于静力结果选用荷载类型为Zero-Based和Goodman应力修正模型进行疲劳分析。分析表明原模型结构的最小疲劳寿命为200万次,最小安全系数为1.26>1,整体节点的疲劳寿命满足要求。分别建立斜腹杆和竖腹杆螺栓缺失模型,对模型疲劳分析表明:斜腹杆螺栓缺失将使应力增加5.24%,降低疲劳安全系数6.44%;竖腹杆螺栓缺失将使应力增加5.95%,降低疲劳安全系数7.28%,对于桥梁的耐久性较为不利。

Taking Baiyang Yangtze River Bridge in Hubei Province as the engineering background,the influence of high-strength bolt missing on the overall joint fatigue performance is studied.ANSYS Workbench is used to build the finite element model of the whole joint.Based on the static results,zero based and Goodman stress correction models are selected for fatigue analysis.The analysis shows that the minimum fatigue life of the original model structure is 2 million times,and the minimum safety factor is 1.26>1.The fatigue life of the whole joint meets the requirements.The models of bolt missing of diagonal web member and vertical web member are established respectively.The fatigue analysis of the models shows that:the bolt missing of diagonal web member will increase the stress by 5.24%and reduce the fatigue safety factor by 6.44%;the bolt missing of vertical web member will increase the stress by 5.95%and reduce the fatigue safety factor by 7.28%,which is unfavorable to the durability of bridges.