西南交通大学学报
西南交通大學學報
서남교통대학학보
JOURNAL OF SOUTHWEST JIAOTONG UNIVERSITY
2015年
2期
294-299
,共6页
叶华文%黄云%王义强%强士中
葉華文%黃雲%王義彊%彊士中
협화문%황운%왕의강%강사중
桥梁缆索%镀锌钢丝%腐蚀疲劳%临界域法%应力集中系数
橋樑纜索%鍍鋅鋼絲%腐蝕疲勞%臨界域法%應力集中繫數
교량람색%도자강사%부식피로%림계역법%응력집중계수
bridge cable%galvanized steel wire%corrosion fatigue%TCD (theory of critical distances)%stress concentration factor
为评估桥梁钢丝服役期间的腐蚀疲劳性能,采用临界域法,根据钢丝腐蚀坑局部应力梯度求解临界距离。采用精细有限元法,建立了钢丝腐蚀疲劳寿命预测模型;通过圆形、三角形和含切口的三角形3种形状腐蚀坑钢丝的疲劳试验,获得了它们的疲劳寿命,并与疲劳寿命的预测结果进行比较。研究结果表明:轴向应力分布决定钢丝的疲劳强度;临界距离随应力集中效应增强而减小;腐蚀钢丝的剩余寿命可根据应力集中系数评估,应力集中系数大于3的腐蚀钢丝应考虑更换。
為評估橋樑鋼絲服役期間的腐蝕疲勞性能,採用臨界域法,根據鋼絲腐蝕坑跼部應力梯度求解臨界距離。採用精細有限元法,建立瞭鋼絲腐蝕疲勞壽命預測模型;通過圓形、三角形和含切口的三角形3種形狀腐蝕坑鋼絲的疲勞試驗,穫得瞭它們的疲勞壽命,併與疲勞壽命的預測結果進行比較。研究結果錶明:軸嚮應力分佈決定鋼絲的疲勞彊度;臨界距離隨應力集中效應增彊而減小;腐蝕鋼絲的剩餘壽命可根據應力集中繫數評估,應力集中繫數大于3的腐蝕鋼絲應攷慮更換。
위평고교량강사복역기간적부식피로성능,채용림계역법,근거강사부식갱국부응력제도구해림계거리。채용정세유한원법,건립료강사부식피로수명예측모형;통과원형、삼각형화함절구적삼각형3충형상부식갱강사적피로시험,획득료타문적피로수명,병여피로수명적예측결과진행비교。연구결과표명:축향응력분포결정강사적피로강도;림계거리수응력집중효응증강이감소;부식강사적잉여수명가근거응력집중계수평고,응력집중계수대우3적부식강사응고필경환。
Based on the theory of critical distances,critical distance to influence fatigue damage zone determining was solved in light of the notch stress gradient of corroded wires so as to estimate the fatigue performance of bridge wires in service. FEM (finite element method)was used to propose a fatigue assessment to predict the life of corroded wires. The fatigue lives were obtained by fatigue tests for corroded galvanized steel wires on three corrosion levels as well as wire specimens with an artificial pit,including to round pit,triangle pit or triangle pit with a notch,and compared with the predicted lives. The research results show that the axial stress distribution has a significant effect on the fatigue strength of corroded bridge wires. The critical distance decreases when stress concentration raises. Stress concentration factor (SCF)is recommended to be an estimation indicator of residual life of wires,and the corroded wires with an SCF of above 3 should be replaced.