高速铁路节段预制简支箱梁构造设计和力学性能分析

以国外某高速铁路工程24.6~32.6 m节段预制简支箱梁为研究对象,将节段划分为端头节段(D类)、渐变节段(G类)及标准节段(B类),结合当地运输及架设条件,通过改变各节段数量组成相同梁高、不同跨径的简支箱梁;结合节段预制简支箱梁特点,论述剪力键构造、预应力布置及临时连接设计要点;采用MIDAS/civil、MIDAS FEA、ANSYS与BSAS程序建立模型,对节段预制简支箱梁的力学性能进行检算分析;重点分析胶接缝对简支箱梁受力性能的影响,节段预制简支箱梁抗弯、抗剪折减系数以及抗裂安全系数取值。分析结果表明,节段预制简支箱梁结构受力和变形满足规范要求,适用于高速铁路工程。

Structure Design and Mechanical Property Analysis of Segmental Precast Simply Supported Beam of High-Speed Railway

Based on a foreign high-speed railway project,24.6~32.6 m segmental precast simply supported beam was taken as the research object.The beam was divided into three types of segments,end segment(type D),transition segment(type G)and standard segment(type B).Considering the local transportation and construction situation,beams with different span and same height were combined.According to the feature of the beam,the arrangement of shear keys,precast tendon and temporary stressing bed were analyzed.The finite element model was established by MIDAS/civil,MIDAS FEA,ANSYS and BSAS.The mechanical property of the beam was calculated and analyzed in terms of the strength,service stage and construction stage.The effect of epoxy joints on the mechanical property of the beam was focused.This paper discoursed the bending resistance reduction value,shear resistance reduction value and anti-crack safety value.The results show that the strength and deformation of segmental precast simply supported beam meets with code requirements,and the structure is adaptable to high-speed railway project.