摘要
为评估钢桥面板的疲劳寿命，在某大桥钢箱梁1/4跨截面的顶板与U肋连接焊缝处和横隔板弧形缺口处布置应力测点，进行24 h疲劳应力监测。根据实测数据，利用雨流计数法计算得到疲劳应力谱，并基于BS 5400规范对各应力测点的疲劳损伤状态进行评估。结果表明：横隔板弧形缺口周边测点的应力水平相对较高；各应力测试点以低幅值应力循环为主，其中应力幅为2~10 MPa的循环次数占90%以上，但最大应力幅值均超过了BS 5400规范规定的产生疲劳损伤的极限值。疲劳寿命分析表明，顶板与U肋纵向连接焊缝过焊孔处易产生靠近顶板部位的疲劳裂纹，横隔板与U肋腹板连接焊缝的疲劳寿命较低。
In order to evaluate the fatigue life of a steel bridge deck, stress measuring points were set near the weld of the roof connected to the U-rib and the arc-shaped notch of the diaphragm plate across a quarter of a bridge ’ s steel box girder, and the fatigue stress was monitored for 24 hours. According to the measured data, the fatigue stress spectra were calculated with the rain-flow counting method. Based on the BS 5400 specification, the fatigue damage state of the stress measuring points was evaluated. The results show that the stress level of the measuring points near the arc-shaped notch of the diaphragm plate was relatively high. Each stress measuring point was mainly a low-rising stress cycle and the cycles of 2 to 10 Mpa stress amplitude accounted for more than 90%. However, the maximum stress amplitude exceeded the limit of fatigue damage stipulated by the BS 5400 specification. Fatigue life analysis shows that fatigue cracks in the weld of the roof connected to the U-rib easily occurred near the roof area at the welding hole, and the fatigue life of the weld of the diaphragm plate connected to the U-rib’ s web was short.
出处
《河海大学学报（自然科学版）》
CAS
CSCD
北大核心
2014年第5期422-426,共5页
Journal of Hohai University(Natural Sciences)
基金
江苏省交通科学研究计划(2012Y13)
关键词
钢桥面板
实测应变
疲劳应力谱
疲劳寿命
steel bridge deck
measured strain
fatigue stress spectra
fatigue life
