| 引用本文: | 阳逸鸣,彭建新,张建仁.考虑多因素作用下的RC梁抗力时空退化模型[J].哈尔滨工业大学学报,2017,49(9):58.DOI:10.11918/j.issn.0367-6234.201611077 |
| YANG Yiming,PENG Jianxin,ZHANG Jianren.Resistance degradation model of RC beam under the influence of many factors[J].Journal of Harbin Institute of Technology,2017,49(9):58.DOI:10.11918/j.issn.0367-6234.201611077 |
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| 摘要: |
| 为研究钢筋混凝土结构锈蚀后的力学性能和抗力退化规律，基于RC梁加速锈蚀试验结果，首先综合考虑均匀锈蚀和点蚀同时发生的影响，对钢筋截面面积的时变模型进行分析，其次探讨裂缝宽度与氯离子扩散系数及RC梁抗力的关系，随后考虑受拉主筋锈蚀不均衡的影响，对结构抗力计算模型进行讨论，最后基于材料性能和结构尺寸的空间变异性，建立RC梁抗力时空退化模型，并对桥梁服役100 a后的抗力进行预测.研究发现：当考虑各参数的空间变异性时，不考虑裂缝影响得到的抗力值比考虑裂缝影响得到的抗力值高了9.91%；考虑各参数空间变异性时的抗力值比不考虑时下降了14.68%；适当的选取波动系数和单元尺寸对考虑结构各参数的空间变异性十分重要；潮汐区和浪溅区环境下结构的剩余抗力分别为初始抗力的43.23%和36.45%，较海岸线大气区环境下的抗力值分别下降了6.73%和21.35%，因此在结构服役期间，应尽量做好防腐措施，减少氯离子侵蚀对结构耐久性的破坏.
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| 关键词: 锈蚀梁 抗力退化 钢筋截面面积 裂缝 锈蚀不均衡 空间变异性 |
| DOI：10.11918/j.issn.0367-6234.201611077 |
| 分类号:TU375 |
| 文献标识码:A |
| 基金项目:国家重点基础研究发展计划(2015CB057701)；国家自然科学基金面上项目(0,1)；湖南省教育厅优秀青年项目(15B015)；长沙理工大学交通基础设施安全风险管理行业重点实验室开放基金(16BCX08) |
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| Resistance degradation model of RC beam under the influence of many factors |
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YANG Yiming,PENG Jianxin,ZHANG Jianren
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(Key Laboratory of Bridge Engineering Safety Control by Department of Education (Changsha University of Science and Technology), Hunan Province and Ministry of Education, Changsha 410114, China)
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| Abstract: |
| To study the decline of RC structural resistance and durability caused by chloride ion erosion, based on RC beams accelerated corrosion test, firstly, the model of steel bar section area is analyzed considering the two kinds of uniform corrosion and pitting corrosion at the same time. Secondly, the relationship between the crack width and chloride diffusion coefficient and the resistance of RC beam is established. Then the structural resistance calculation model is discussed under the influence of corroded main bars with different corrosion degree in the same RC beam. Finally, considering spatial variability of material properties and structure size, the time-spatial-varying degradation model of RC beams resistance is built and the resistance of the bridge after 100 years of service is predicted. The results show that when the spatial variability of the parameters is considered, the resistance value wihtout considering the influence of the crack is 9.91% higher than the corresponding value considering the influence of crack. Considering the spatial variability of the parameters, the resistance of RC beam is decreased by 14.68% when compared with that without consideration. The appropriate choice of the fluctuation coefficient and the unit size to consider the spatial variability of the parameters of RC structure is very important for the safety evaluation of RC beam. The residual resistance of the structure in tidal area and splash zone is 43.23% and 36.45% of the initial value, compared with the atmospheric environment of the coastline, decreased by 6.73% and 21.35%, respectively. Therefore, in the service of the structure, corrosion protection measures should be done well to reduce the damage of the structure durability of chloride ion erosion.
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| Key words: corroded beams resistance degradation cross-sectional area crack corrosion imbalance spatial variability |
