大跨度RPC铁路简支箱梁有效宽度研究  

Research on Effective Width of Long Span RPC Simple Railway Box Girder

作　　者：吴延伟[1] WU Yanwei(China Railway First Survey ＆ Design Institute Group Co.,Ltd.,Xi＇an 710000,Chin)

机构地区：[1]中铁第一勘察设计院集团有限公司,西安710000

出　　处：《交通科技》2018年第4期82-85,共4页Transportation Science & Technology

摘　　要：RPC箱梁轻薄的截面使其翼缘剪力滞效应显著,通过对72m铁路简支箱梁采用有限元程序ANSYS进行三维分析,得到不同荷载工况、梁高、顶板厚度对跨中断面顶、底板剪力滞效应的影响规律,计算出对应的有效宽度系数,并与现行设计规范相关有效宽度计算结果比对。研究表明:(1)跨中断面在二期铺装荷载作用下剪力滞效应最显著;(2)随着高跨比的增大,跨中断面剪力滞效应逐渐增大;(3)增加顶板厚度可有效减小跨中断面剪力滞效应;(4)箱梁顶板有效宽度较规范计算偏小;(5)降低二期恒载可以改善顶板有效宽度折减。The thin section of the RPC box girder makes the shear lag effect of the flange significantly.Through the three-dimensional analysis of the finite element program ANSYS for the 72 mrailway simple box girder,the influence of different load conditions,beam height and roof thickness on the shear lag effect in top and bottom plate at mid-span cross sectionis studied.The influence law of the shear lag effect of the floor is calculated and the corresponding effective width coefficient is calculated and compared with the effective width calculation result related to the current design code.The results show that：（1）Shear lag effect is the most significant in the second section of pavement under crosssection;（2）With the increase of the span ratio,the shearing lag effect of mid-span cross sectionincreases gradually;（3）Increasing the thickness of roof can effectively reduce the shear lag effect of the cross section;（4）The effective width of the box girder roof is smaller than the standard calculation;（5）Reducing the second-stage deadweight can improve the effective roof width reduction.

关 键 词：RPC 铁路简支梁 剪力滞 有效宽度 规范 

分 类 号：U442[建筑科学—桥梁与隧道工程]