摘要
为了深入研究折线配筋先张梁的力学性能,在优化选定的折点半径基础之上,以Ansys有限元分析软件为工具,采用分离式模型,建立了基于三维实体预应力筋单元的折线配筋先张梁非线性有限元分析模型,探讨了折点弯折角度、预应力筋布置间距、混凝土强度等级等结构、材料参数变化时先张梁折点局部应力状态与变化规律。研究结果表明:折点弯折角度对折点处σymax影响较小,但较大折角会使折点应力集中程度得到一定缓和;预应力筋间距虽然对折点处应力分布状态影响不大,但需要注意间距较小时在横向上可能产生的应力叠加现象;由于应力水平较低时不同强度等级混凝土的本构关系差别不大,对于预应力筋折点采用优化半径的先张梁,混凝土强度等级变化对折点处应力状态影响较小。
For the sake of further researching the mechanical property of pretensioned concrete beams with prestressed reinforcement in polyline, the 3D nonlinear finite element model was established by ANASYS software. This model adopted separate finite element model, and the polyline prestressed reinforcement of the pretensioned beam was simulated by body element while the comer radius selects the optimized radius size. The influence of bend degree α, reinforcement spacing D and cement concrete strength grade, etc. at the polyline prestressed reinforcement inflection point of pretensioned beam were discussed. The results show that （ 1 ） the influence of α on the maximum vertical stress O＇ymax is minor, while the larger a can help to relief the stress concentration; （2） the influence of reinforcement spacing D on local stress distribution is slight, but the smaller D may induce stress superposition in the transverse direction; （3） to the pretensioned beam with optimized radius size at inflection point, the cement concrete strength grade has smaller influence on the local stress distribution since the constitutive relation at lower stress levels is no significant difference between different strength grades.
出处
《公路交通科技》
CAS
CSCD
北大核心
2012年第1期75-79,共5页
Journal of Highway and Transportation Research and Development
基金
住房和城乡建设部科学技术项目计划(2011-K2-23)
湖北省教育厅科学技术研究项目(Q20111314)
关键词
桥梁工程
应力分析
有限元法
折线配筋先张梁
应力集中
结构参数
材料参数
Key words： bridge engineering
stress analysis
finite element method
pretensioned concrete beam withprestressed reinforcement in polyline
stress concentration
structural parameters
material parameters.
