【作者】 吴志添； 王渠； 吴庆雄； 陈康明；

【Author】 WU Zhi-tian;WANG Qu;WU Qing-xiong;CHEN Kang-ming;School of Civil Engineering,Fuzhou University;Fujian Provincial Key Laboratory on Multi-Disasters Prevention and Mitigation in Civil Engineering;

【机构】 福州大学土木工程学院； 福建省土木工程多灾害防治重点实验室；

【摘要】 在2013年4月的日常的检修期间,发现在某主跨为136m的中承式钢管混凝土桁式拱桥的主管和支管的连接节点处存在裂缝。以中承式钢管混凝土桁式拱桥拱肋为研究对象,基于热点应力法对钢管混凝土拱肋K型节点疲劳进行评价。研究结果表明:基于热点应力法得到的钢管混凝土K型节点相贯线附近的应力集中系数在1.2到2.3之间,当弦杆填充混凝土时,应力集中变小,随着杨氏模量的减小,热点应力略有增大;考虑到精度和计算时间之间的平衡,1.2mm网格相对是比较理想的划分;比较CIDECT和JSSC,两者在预测疲劳寿命的差异较大;当平均日流量为1400辆时,采用S-N曲线E类(JSSC)计算的疲劳寿命与实际情况最接近,其疲劳寿命是17.6年。更多还原

【Abstract】 During the routine maintenance period in April 2013, there were cracks in the connection of arch chord and branch of the 136 m concrete-filled steel tubular(CFST) arch bridge. Based on the hot spot stress method, the fatigue evaluation of the arch rib K joints of the steel tube is studied. The results show that stress concentration factors(SCFs) is between 1.2 and 2.3 of CFST K-joint around intersecting line, based on the hot stress method. When the chord is filled with concrete, the stress concentration becomes smaller, and with the decrease of young’s modulus, the hot-spot stress increases slightly. Considering the balance between accuracy and calculation time, 1.2 mm grid is relatively ideal partition. Compared with CIDECT and JSSC, the difference in predicting fatigue life was large. The S-N curve E class(JSSC) was used when the average daily truck flow was 1400. The fatigue life calculated by class E(JSSC) is the closest to the actual situation, and its fatigue life is 17.6 years.更多还原