摘要
为研究活性粉末混凝土(RPC)箱梁替代普通混凝(NC)箱梁的技术可行性,以32m跨标准NC箱梁为初始模型,采用ANSYS软件中零阶法与随机搜索法对RPC箱梁进行优化设计研究。在RPC箱梁基本截面尺寸优化的基础上,沿箱梁纵向设置厚0.15m的横隔板,建立无横隔板、横隔板间距8m与横隔板间距4m的RPC箱梁模型,对比分析各模型受力性能,并对优化的多横隔板RPC箱梁与NC箱梁的静、动力特性及经济性等进行对比。结果表明:横隔板间距为4m的RPC箱梁受力性能最优;与NC箱梁相比,RPC箱梁竖向刚度增大2.57%,竖向自振频率增大18.48%;RPC箱梁自重比NC箱梁减少32.14%,预应力筋用量减小19.78%;在动荷载作用下,与NC无砟轨道梁桥体系相比,RPC梁桥体系各构件竖向位移均减小,竖向加速度局部增大,但整体呈下降趋势;RPC箱梁具有更好的经济性。
To study the technical possibility of using reactive powder concrete(RPC)box girder to replace the normal concrete(NC)box girder,the initial model,a standard NC box girder with span length of 32 m,was established,to which the zero-order hold method and random search method in ANSYS software were employed to carry out design optimization study for RPC box girder.Based on the optimization of basic cross section dimension of RPC box girder,the 0.15 m thick diaphragms were installed along the longitudinal direction of the box girder.The RPC box girder models without diaphragms,with diaphragms at intervals of 8 m and with diaphragms at intervals of 4 m were established,the load bearing behaviors of these models were contrastively analyzed,and the static and dynamic property as well economic performance of the optimized multi-diaphragm RPC box girder and NC box girder were compared.The results show that the load bearing performance of the RPC box girder with diaphragms at intervals of 4 m is the optimal option.Compared with NC box girder,the vertical stiffness of RPC box girder increases 2.57%and the vertical natural vibration frequency increases 18.48%.The self-weight of RPC box girder decreases 32.14%and the amount of prestressing tendons used decreases 19.78%.Under the action of moving loads,compared to NC ballastless track girder bridge,the vertical displacement of each component of RPC girder bridge decreases,the vertical acceleration locally increases,but the overall acceleration reveals decreasing trend.The RPC box girder exhibits better economic performance.
作者
胡红波
彭鑫
刘高
HU Hong-bo;PENG Xin;LIU Gao(Changsha Road and Bridge Construction Co.,Ltd.,Changsha 410013,China)
出处
《世界桥梁》
北大核心
2018年第6期6-10,共5页
World Bridges
关键词
高速铁路桥
箱形梁
活性粉末混凝土
优化设计
受力性能
有限元法
high-speed railway bridge
box girder
reactive powder concrete
optimization design
load bearing performance
finite element method
