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)
2013年
4期
817-822
,共6页
李自林%丁宏毅%邢颖%薛江
李自林%丁宏毅%邢穎%薛江
리자림%정굉의%형영%설강
钢-混凝土组合桁架%栓钉%疲劳荷载%有限元
鋼-混凝土組閤桁架%栓釘%疲勞荷載%有限元
강-혼응토조합항가%전정%피로하재%유한원
steel-concrete composite truss%studs%fatigue loads%finite element
为研究钢-混凝土组合桁架在疲劳荷载下的受力性能,提高组合桁架的疲劳寿命,为疲劳设计提供一定依据,以某大跨桥梁为基础设计6组组合桁架构件,采用有限元计算软件 ANSYS和名义应力理论相结合的方法对其进行数值模拟和研究。由精细有限元分析模拟疲劳荷载引起单元的损伤,进而获得更加准确的修正S-N曲线。通过对模型施加常幅疲劳荷载,计算其在不同配筋率和混凝土抗压强度下的疲劳寿命,考察不同影响因素对组合桁架疲劳寿命的影响。结果表明,混凝土强度增加1个等级(约8%),疲劳寿命提高约20%;而配筋率也以约8%的速率增加时,疲劳寿命只提高约0.3%。混凝土抗压强度和配筋率均为影响组合桁架疲劳性能的因素,构件的疲劳寿命随混凝土抗压强度和配筋率的提高而增长,其中混凝土抗压强度的影响相比配筋率更为显著。研究结果可为组合桁架桥梁的设计提供了依据。
為研究鋼-混凝土組閤桁架在疲勞荷載下的受力性能,提高組閤桁架的疲勞壽命,為疲勞設計提供一定依據,以某大跨橋樑為基礎設計6組組閤桁架構件,採用有限元計算軟件 ANSYS和名義應力理論相結閤的方法對其進行數值模擬和研究。由精細有限元分析模擬疲勞荷載引起單元的損傷,進而穫得更加準確的脩正S-N麯線。通過對模型施加常幅疲勞荷載,計算其在不同配觔率和混凝土抗壓彊度下的疲勞壽命,攷察不同影響因素對組閤桁架疲勞壽命的影響。結果錶明,混凝土彊度增加1箇等級(約8%),疲勞壽命提高約20%;而配觔率也以約8%的速率增加時,疲勞壽命隻提高約0.3%。混凝土抗壓彊度和配觔率均為影響組閤桁架疲勞性能的因素,構件的疲勞壽命隨混凝土抗壓彊度和配觔率的提高而增長,其中混凝土抗壓彊度的影響相比配觔率更為顯著。研究結果可為組閤桁架橋樑的設計提供瞭依據。
위연구강-혼응토조합항가재피로하재하적수력성능,제고조합항가적피로수명,위피로설계제공일정의거,이모대과교량위기출설계6조조합항가구건,채용유한원계산연건 ANSYS화명의응력이론상결합적방법대기진행수치모의화연구。유정세유한원분석모의피로하재인기단원적손상,진이획득경가준학적수정S-N곡선。통과대모형시가상폭피로하재,계산기재불동배근솔화혼응토항압강도하적피로수명,고찰불동영향인소대조합항가피로수명적영향。결과표명,혼응토강도증가1개등급(약8%),피로수명제고약20%;이배근솔야이약8%적속솔증가시,피로수명지제고약0.3%。혼응토항압강도화배근솔균위영향조합항가피로성능적인소,구건적피로수명수혼응토항압강도화배근솔적제고이증장,기중혼응토항압강도적영향상비배근솔경위현저。연구결과가위조합항가교량적설계제공료의거。
In order to study the performance of steel-concrete composite trusses under fatigue loads and to improve the fatigue life of the composite trusses , 6 composite truss models of a large span bridge were built and analyzed by ANSYS software combined with the nominal stress method .The damage of elements caused by fatigue loads were simulated by a refined finite element analysis , and more accurate modified S-N curves were obtained .The fatigue life of the models with different rein-forcement ratios and concrete compression strengths under constant amplitude fatigue loading was simulated to study the influence of different factors on the fatigue life of composite trusses .The re-sults showed that when the concrete strength was increased by one grade with a rate of about 8%, the fatigue life was increased by about 20%, while the reinforcement ratio was also increased with the same rate of about 8%, the fatigue life was increased by only about 0.3%.The concrete com-pression strength and the reinforcement ratio were both main influencing factors of the fatigue life . Fatigue life was increased while the concrete compression strength and the reinforcement ratio were increased, and the influence of concrete compression strength was more significant than that of the reinforce ratio .These results provide a basis for the design of composite truss bridges .