广西大学学报(自然科学版)
廣西大學學報(自然科學版)
엄서대학학보(자연과학판)
JOURNAL OF GUANGXI UNIVERSITY (NATURAL SCIENCE EDITION)
2015年
4期
998-1005
,共8页
U肋%疲劳%应力幅%裂纹扩展
U肋%疲勞%應力幅%裂紋擴展
U륵%피로%응력폭%렬문확전
U-rib%fatigue%stress amplitude%crack propagation
为研究车轮行驶位置对钢桥面板U肋对接焊缝疲劳性能的影响,现以江阴长江大桥为研究对象,采用数值模拟的方法,计算了不同车辆轮迹位置作用下U肋对接焊缝处的疲劳应力幅,结合BS5400规范得到了该细节相应位置的疲劳损伤度;建立U肋对接焊缝局部模型,模拟了不同车轮位置作用下疲劳裂纹扩展路径,同时得到了各扩展阶段的裂纹扩展参数。结果表明:车轮位置与焊缝之间距离大于600 mm,可忽略车辆位置对U肋对接焊缝开裂前的疲劳损伤累计;相对于其他部位,U 肋两侧弧形段疲劳损伤严重,易产生疲劳裂纹;随着车轮位置的改变,裂纹扩展路径逐渐由与焊缝平行向与焊缝垂直发展,车轮位置与焊缝之间距离大于750 mm,可忽略车辆位置对U肋对接焊缝开裂后的裂纹扩展影响。
為研究車輪行駛位置對鋼橋麵闆U肋對接銲縫疲勞性能的影響,現以江陰長江大橋為研究對象,採用數值模擬的方法,計算瞭不同車輛輪跡位置作用下U肋對接銲縫處的疲勞應力幅,結閤BS5400規範得到瞭該細節相應位置的疲勞損傷度;建立U肋對接銲縫跼部模型,模擬瞭不同車輪位置作用下疲勞裂紋擴展路徑,同時得到瞭各擴展階段的裂紋擴展參數。結果錶明:車輪位置與銲縫之間距離大于600 mm,可忽略車輛位置對U肋對接銲縫開裂前的疲勞損傷纍計;相對于其他部位,U 肋兩側弧形段疲勞損傷嚴重,易產生疲勞裂紋;隨著車輪位置的改變,裂紋擴展路徑逐漸由與銲縫平行嚮與銲縫垂直髮展,車輪位置與銲縫之間距離大于750 mm,可忽略車輛位置對U肋對接銲縫開裂後的裂紋擴展影響。
위연구차륜행사위치대강교면판U륵대접한봉피로성능적영향,현이강음장강대교위연구대상,채용수치모의적방법,계산료불동차량륜적위치작용하U륵대접한봉처적피로응력폭,결합BS5400규범득도료해세절상응위치적피로손상도;건립U륵대접한봉국부모형,모의료불동차륜위치작용하피로렬문확전로경,동시득도료각확전계단적렬문확전삼수。결과표명:차륜위치여한봉지간거리대우600 mm,가홀략차량위치대U륵대접한봉개렬전적피로손상루계;상대우기타부위,U 륵량측호형단피로손상엄중,역산생피로렬문;수착차륜위치적개변,렬문확전로경축점유여한봉평행향여한봉수직발전,차륜위치여한봉지간거리대우750 mm,가홀략차량위치대U륵대접한봉개렬후적렬문확전영향。
In order to study the fatigue effect of the orthotropic steel bridge deck of U-rib butt weld under different wheels position, which use the numerical simulation method and as the Jiangyin Yangtze River Bridge for research object. First use the general-purpose finite element software to analysis the fatigue stress amplitude of U-rib butt welds under different wheels position, which com-bined with BS5400 standard to calculate the degree of fatigue damage for this fatigue details, and then use FRANC2 D/L software to simulate the changing rules of crack propagation path under differ-ent wheels positions. The results show that: the distance of wheels and U-rib is greater than 600 mm, it can ignore the fatigue damage cumulative to butt weld; compared to other sites, the fatigue damage of the sides of U-rib arc-shaped segment is serious, which easy to produce fatigue crack;with the change of the position of the wheels, the crack propagation path change from parallel to the butt weld to the vertical to the butt weld gradually, and while the distance of wheels and U-rib is greater than 750mm, the effect of wheels position to crack propagation can be ignored.