钢筋钢纤维混凝土梁疲劳全过程分析及寿命预测  

Full-range analysis and life prediction of steel fiber reinforced concrete beam subjected to fatigue loading

作　　者：谷志强[1] 高丹盈[1] 王建召 李昊璋 胡玉博 GU Zhiqiang;GAO Danying;WANG Jianzhao;LI Haozhang;HU Yubo(Yellow River Laboratory,Zhengzhou University,Zhengzhou 450002,China;School of Civil Engineering,Zhengzhou University,Zhengzhou 450002,China)

机构地区：[1]郑州大学黄河实验室,河南郑州450002 [2]郑州大学土木工程学院,河南郑州450002

出　　处：《建筑结构学报》2024年第5期164-172,共9页Journal of Building Structures

基　　金：国家自然科学基金面上项目(51978629)。

摘　　要：为研究钢筋钢纤维混凝土梁的疲劳损伤演化过程,并对其疲劳寿命进行预测,依据钢筋钢纤维混凝土梁疲劳试验结果,基于梁受压和受拉区钢纤维混凝土以及受拉钢筋的疲劳损伤演化特性,采用分段线性方法,建立钢筋钢纤维混凝土梁疲劳全过程分析及寿命预测模型,并与试验结果对比进行验证。采用该模型分析钢纤维混凝土梁的混凝土、钢筋应变以及受拉钢筋截面面积随疲劳循环次数的退化规律,得到不同疲劳循环次数后试验梁的剩余承载力。结果表明:钢纤维能够显著提高梁的疲劳性能,试验梁的受拉钢筋截面面积随疲劳循环次数增加呈两阶段减小趋势,而受压区混凝土和受拉钢筋的应变以及梁剩余承载力呈三阶段发展模式,42根钢筋钢纤维混凝土梁的试验疲劳寿命与预测疲劳寿命比值的均值为0.953,变异系数为0.284,整体符合较好。This paper explore the fatigue damage evolution process and predict the fatigue life of steel fiber reinforced concrete(SFRC)beam.Based on the fatigue damage evolution characteristics of SFRC in compression zone and the tensile zone and tensile reinforcement of beam,combined with the fatigue test results of SFRC beam,the full-range analysis and life prediction model of SFRC beam subjected to fatigue loading was established by the method of segment linearization.Subsequently,the results were compared to the test results for validation.Based on the proposed model,the degradation law of concrete and tensile reinforcement strains,and cross-sectional area of tensile reinforcement of SFRC beams with the fatigue cycles were analyzed,and the residual ultimate capacity of SFRC beam after different fatigue cycles was obtained.The results show that steel fibers can significantly improve the fatigue performance of beams.The cross-sectional area of tensile steel bars in the beam shows a two-stage decreasing trend with increasing fatigue cycles,while the strains of concrete in the compression zone and tensile steel bars,as well as the remaining capacity of the beam,exhibit a three-stage development pattern.The average ratio of experimental fatigue life to predicted fatigue life of 42 SFRC beams is 0.953,with a coefficient of variation of 0.284,indicating good overall agreement.

关 键 词：钢纤维混凝土梁 疲劳试验 全过程分析 寿命预测 

分 类 号：TU375[建筑科学—结构工程] TU317.1