长期轴压下有初应力的CFRP约束混凝土柱应力-应变关系分析

发布时间：2018-04-22 11:40

本文选题：CFRP + 约束混凝土柱　；参考：《土木工程学报》2016年09期

【摘要】：为了研究有初应力的CFRP约束混凝土柱在长期荷载作用下的应力-应变关系,对有不同初应力的12个CFRP约束混凝土柱进行了三种模式的长期荷载试验,观测了初应力和长期荷载对CFRP约束柱的长期变形、峰值点应力、应变及应力-应变曲线特征的影响。试验结果表明,在长期荷载作用下,包裹CFRP后的构件比未包裹的长期变形小,并随初应力水平的提高,构件的长期变形增大;长期荷载对峰值点应力、应变的影响随初应力水平的提高而增大,在初应力水平较高时有减小的趋势;与短期荷载相比,长期荷载作用后的应力-应变曲线特征没有发生明显变化。在此基础上,选取ACI 209-92模型和Findley模型分别作为混凝土和CFRP的徐变模型,提出了CFRP约束混凝土柱长期变形的计算方法,并针对三种加载模式,分别建立了长期荷载下CFRP约束混凝土柱的应力-应变关系计算模型,结果表明模型的计算曲线与试验曲线吻合较好。
[Abstract]:In order to study the stress-strain relationship of CFRP confined concrete columns with initial stress under long-term load, three kinds of long-term load tests were carried out on 12 CFRP confined concrete columns with different initial stresses. The effects of initial stress and long-term load on the long-term deformation, peak stress, strain and stress-strain curves of CFRP confined columns are observed. The experimental results show that the long-term deformation of the members wrapped with CFRP is smaller than that of the unwrapped members under the long-term load, and the long-term deformation of the members increases with the increase of the initial stress level, and the stress of the peak point is increased by the long-term load. The effect of strain increases with the increase of initial stress level, and decreases when the initial stress level is higher, and the characteristics of stress-strain curve after long term load have no obvious change compared with short term load. On this basis, ACI 209-92 model and Findley model are selected as creep models of concrete and CFRP respectively, and the calculation method of long-term deformation of concrete columns confined by CFRP is put forward, and three loading modes are proposed. The stress-strain relationship models of CFRP confined concrete columns under long term load are established respectively. The results show that the calculated curves are in good agreement with the experimental curves.
【作者单位】：西南交通大学;西南交通大学交通隧道工程教育部重点实验室;东南大学;
【基金】：国家自然科学基金(51108389) 国家留学基金(20123022)
【分类号】：TU377.9

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