混凝土帆布与CFRP条带联合加固方形截面混凝土短柱轴心受压力学性能

Mechanical properties of square concrete short columns strengthened by concrete canvas and CFRP strips under axial compression

  • 摘要: 通过混凝土帆布(CC)与碳纤维增强树脂复合材料(CFRP)条带联合加固混凝土方柱轴压试验,研究了纤维条带约束率、CFRP宽度与间距、层数对混凝土方柱轴压力学性能的影响,分析加固后混凝土方柱的破坏形态、承载力、耗能能力及变形能力。研究结果表明:CC的加入可以缓解角部应力集中,明显提高试件的变形能力,改善柱的破坏形态;条带宽度与间距对试件承载力和耗能能力的影响归结于纤维条带约束率,随着纤维条带约束率与CFRP层数的增加,试件的承载能力与耗能能力不断提高;当纤维条带约束率为0.5、宽度与间距为50 mm时,承载力与耗能能力最大。在试验研究的基础上,对有效约束面积变化进行理论分析,得出CC在联合加固中起到的作用,并建立联合加固混凝土方柱轴心受压承载力模型,通过误差分析可知,该模型具有较高的预测精度。

     

    Abstract: Through the axial compression test of concrete square columns which strengthened by concrete canvas (CC) and carbon fiber reinforced polymer (CFRP) strips, the influences of restraint rate, width and spacing of CFRP, and number of layers on the mechanical property of the concrete square column were studied. The failure form, bearing capacity, energy consumption capacity and deformation capacity of the reinforced concrete square column were analyzed. The research results show that the addition of CC can alleviate the stress concentration at the corners, significantly increase the deformation ability of the specimen, and improve the failure form of the column. The influence of width and spacing of the strips on the bearing capacity and energy dissipation capacity of the specimen is attributed to the restraint rate of the fiber strips. With the increase of the strip restraint rate and the number of CFRP layers, the load-bearing capacity and energy consumption capacity of the specimens continue to increase. When the fiber restraint ratio is 0.5, the bearing capacity is the largest when the width and spacing are 50 mm. Based on the experimental research, a theoretical analysis of the effective constrained area change was carried out, and the role of CC in joint reinforcement was obtained, and the axial compression bearing capacity model was established. The error analysis shows that the model has high prediction accuracy.

     

/

返回文章
返回