北京交通大学学报2024，Vol.48Issue(6)：81-92,12.DOI:10.11860/j.issn.1673-0291.20230151
温度荷载下全断面纤维混凝土封闭结构力学特性研究
Study on mechanical characteristics of full-section fiber reinforced concrete seal structure under thermal loads
摘要
Abstract
This study investigates the mechanical characteristics of full-section fiber-reinforced con-crete sealed structures under different temperature loads.A simulation model of the CRTS Ⅲ slab bal-lastless track and full-section fiber-reinforced concrete sealed structure is established using finite ele-ment software.The accuracy of the model is validated by field data from the Weifang-Yantai high-speed railway.The effects of overall thermal load,temperature gradient load,and temperature cyclic load on the stress and strain cloud maps of full section fiber-reinforced concrete sealed structures are analyzed.Additionally,the variation in stress distribution along the longitudinal and lateral directions under these loads is studied.The results indicate that thermal loads have a significant impact on the full-section waterproof sealed structure of high toughness concrete.Under the overall thermal loads,the central area of the base plate is the primary temperature-sensitive region,while the expansion joint position of the track structure is highly sensitive to temperature changes.The deformation of the track structure due to temperature gradient loads is a major influencing factor on the stress distribution of the full-section fiber-reinforced concrete sealed structure.The edge of the base plate exerts a lateral shear effect on the structural layer,highlighting the need for stringent construction quality control to mini-mize interlayer contact damage.Strain hysteresis is observed in the full-section fiber-reinforced con-crete sealed structure under cyclic temperature loading.The hysteresis loop size indicates that the struc-tural layers at the shoulder and base plate edge are prone to fatigue failure.Under cyclic temperature loads,stress and temperature gradients vary with depth and time,with the temperature gradient being notably larger within 0.02 m of the structural floor,marking this region as an unfavorable area for stress distribution.关键词
高速铁路/全断面纤维混凝土封闭结构/无砟轨道/有限元分析/温度荷载/滞回圈Key words
high-speed railway/full-section fiber reinforced concrete sealed structure/ballastless track/finite element analysis/thermal load/hysteresis loop分类
交通工程引用本文复制引用
郭强,姚明昕,钱忠霞,徐爱民,肖宏..温度荷载下全断面纤维混凝土封闭结构力学特性研究[J].北京交通大学学报,2024,48(6):81-92,12.基金项目
国家重点研发计划(2023YFB2604302) （2023YFB2604302）
山东铁投集团科技计划(TTKJ2021-07)National Key R&D Plan(2023YFB2604302) （TTKJ2021-07）
Shandong Railway Investment Group Technology Plan(TTKJ2021-07) （TTKJ2021-07）
