摘要
为了克服传统预应力混凝土主梁、钢主梁、钢-混凝土组合主梁由于材料和结构本身缺陷所引起的病害,提出了适用于(特)大跨径桥梁且无横向表面受拉接缝的钢-UHPC(Ultra-high Performance Concrete)轻型组合桥梁结构。为验证轻型组合梁用于斜拉桥的可行性,建立了空间有限元模型进行静力性能分析和疲劳应力幅计算,并制作了9个足尺条带模型试验梁,开展了静载试验研究。研究结果表明:受拉钢筋配筋率、钢筋直径、直线型纤维直径和长度对UHPC的初裂应力影响不大,而纤维带端钩能显著提高初裂应力;端钩型、直线型纤维UHPC试验梁正弯矩初裂应力分别为19.4,10.6 MPa,前者高出后者83%,负弯矩初裂应力分别为13.8,8.4 MPa,前者高出后者64%;正常使用极限状态时,端钩纤维试验梁正负弯矩初裂应力分别为华夫板下缘、上缘频遇组合拉应力的1.45倍、1.66倍;承载能力极限状态时,端钩纤维试验梁正负弯矩名义拉应力试验值分别为华夫板下缘、上缘基本组合名义拉应力的2.1倍、2.4倍;基于S-N曲线预测UHPC华夫桥面板疲劳寿命远大于200万次。
To avoid the problems of prestressed concrete girders,steel girders,steel-concrete composite bridge girders,which caused by inherent flaws of traditional material and the structure,propose an innovative lightweight steel-UHPC composite bridge girder appropriate for long span bridges.To verify the feasibility of steel-UHPC composite bridge girders used in cable stayed bridge,a finite element model was built to analyze the static performance and to calculatethe stress range of fatigue and 9full size stripe test specimens were designed to process static tests.The results show that tensile reinforcement ratios,steel bar diameter,diameter and length of linear fiber have little effect on first crack stress,while the first crack stress is significantly improved by steel fiber with hooked end.In positive bending moment,first crack stress of UHPC specimens with hooked fiber and linear fiber are respectively 19.4 MPa and 10.6 MPa,and the former is 83% higher than the latter.In negative bending moment,crack stresses of UHPC specimens with hooked fiber and linear fiber are respectively 13.8MPa and 8.4MPa,the former is 64% higher than the latter.In positive and negative bending moment test,the first crack stress of UHPC specimen with hooked fiber are respectively 1.45 and 1.66 times of tensile stress of Waffle deck panel in frequent combinations under serviceability limit state,the nominal tensile stress of UHPC specimen with hooked fiber are respectively 2.1and 2.4times of nominal tensile stresses of Waffle deck panel in fundamental combinations under ultimate limit state.Based on the S-N curves,prediction of fatigue life UHPC Waffle bridge deck is more than 200 million times.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2017年第3期218-225,245,共9页
China Journal of Highway and Transport
基金
国家自然科学基金项目(51178177)
交通运输部重大科技专项项目(2011318494160)
湖南省交通运输厅科技创新项目(201437)
关键词
桥梁工程
华夫桥面板
试验研究
静力性能
钢-UHPC轻型组合桥梁结构
初裂应力
bridge engineering
waffle deck panel
experimental research
static performance
lightweight steel-UHPC composite bridge structure
first crack stress
