摘要
为了提高钢管混凝土桁架梁桥的跨越能力,改善结构内力分布,提出分段预应力钢管混凝土桁架组合梁桥,通过引入分段预应力,即受拉弦杆施加预应力、受压弦杆不施加预应力,以充分发挥钢管混凝土桁架梁桥的综合优势。基于已有的钢管混凝土桁架受弯试验,建立精细化有限元模型,通过对比试验与有限元结果,验证有限元模型的准确性和适用性。在此基础上,考虑预应力度的变化和有无混凝土桥面板的组合作用,建立9个分段预应力钢管混凝土桁架梁的有限元模型,通过数值模拟方法研究其在均布荷载作用下的受弯性能,得到破坏模式、荷载-位移曲线、受弯承载力、抗弯刚度和最大跨中挠度。研究结果表明:分段预应力的设置可以提高结构的抗弯刚度和受弯承载力、减少跨中挠度;随着预应力度的增加;分段预应力钢管混凝土桁架梁的破坏模式从整体受弯破坏变为局部节点破坏,因此预应力度不宜太大。
In order to improve the span capacity of concrete-filled steel tubular truss bridge and the internal force distribution of the structure,a segmental prestressed concrete-filled steel tubular truss composite bridge was put forward,which could give full play to the comprehensive advantages of concrete-filled steel tubular truss bridge by introducing segmental prestressing,that is,tension chords were prestressed and compression chords were not prestressed.A refined finite element model was established based on the existing bending tests of concrete-filled steel tubular trusses,and the accuracy and applicability of the finite element model were verified by comparing the experimental results with the finite element results.On this basis,nine finite element models of segmented prestressed concrete-filled steel tubular truss beams were established considering the change of prestressing degree and the combination of concrete bridge deck or not,and their bending performance under uniform load was studied by numerical simulation,and the failure mode,load-displacement curve,bending capacity,bending rigidity and maximum mid-span deflection of the structure were obtained.The research results show that the setting of segmented prestress can improve the bending rigidity and bending capacity of the structure and reduce the mid-span deflection.With the increase of prestress degree,the failure mode of the structure changes from overall bending failure to joint failure,so the prestressing degree should not be too large.
作者
陈娟
赵剑飞
李秉南
张仁杰
陈驹
CHEN Juan;ZHAO Jianfei;LI Bingnan;ZHANG Renjie;CHEN Ju(College of Civil Aviation,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China;Architectural Design and Research Institute of Southeast University,Nanjing 210096,China;College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2022年第S01期116-123,共8页
Journal of Building Structures
基金
国家自然科学基金项目(52078249)
江苏省“六大人才高峰高层次人才”项目(JZ-009)
江苏省交通运输科技项目(2021Y17-2)
关键词
分段预应力
钢管混凝土
桁架
大跨径
有限元分析
受弯性能
segmental prestressing
concrete-filled steel tube
truss
long span
finite element analysis
bending performance
