预应力钢带加固混凝土柱轴压性能试验研究

发布时间：2018-11-10 14:52

【摘要】：对目前国内钢筋混凝土结构而言，通常会由于设计变更或者建筑使用功能的改变，导致结构受力和变形增大，需要对轴压比不足的框架柱进行加固。预应力钢带打包加固作为一种实用创新型加固技术，可以有效提高混凝土柱的轴压承载能力，且施工简单便捷，成本低，所以在实际工程中有着良好的应用前景。本文通过对9根预应力钢带打包加固的混凝土柱的研究，，对比普通钢筋混凝土柱，展开了在不同加固条件下（钢带间距、钢带层数）钢筋混凝土柱的破坏形态、轴压承载能力和钢带应力应变发展等的分析。试验结果表明，使用预应力钢带加固的混凝土柱轴压承载力明显高于普通钢筋混凝土柱，且其变形能力增强，试验表明钢带间距对承载力的影响最为显著，钢带层数对其变形能力影响显著。根据试验过程，本文系统的研究了预应力钢带打包加固下钢筋混凝土柱的受力机理。结合试验数据，在约束混凝土理论研究的基础上，进行了预应力钢带打包加固钢筋混凝土柱轴压极限承载力公式的推导，结果表明该公式与试验值吻合较好，能够较准确的计算出构件的轴压承载力。为了工程使用方便给出了钢带打包加固轴力可增加的计算公式，该公式能不考虑柱内配筋较快得出经过加固柱子轴压承载力的增加值。通过实际加固工程的应用，对轴压比超限的混凝土柱进行高强钢带预应力打包加固，使轴压比不满足规范限值的构件承载力能力得到提高，从而得以继续使用。通过比较外包钢法和加大截面法，结果表明预应力钢带打包加固方法最为有效，且造价低，施工简便并适合既有工程加固的理论校核，且具有良好的社会经济效益，为日后的进一步研究和实际工程应用提供了理论和实践参考依据。
[Abstract]:For the domestic reinforced concrete structures, the structural stress and deformation will increase due to the design change or the change of the building function, so it is necessary to strengthen the frame columns with insufficient axial compression ratio. As a practical and innovative reinforcement technology, prestressed steel strip packing and strengthening can effectively improve the bearing capacity of concrete columns under axial compression, and the construction is simple and convenient, and the cost is low, so it has a good application prospect in practical engineering. In this paper, through the study of 9 reinforced concrete columns reinforced by prestressed steel strips, the failure patterns of reinforced concrete columns under different reinforcement conditions (steel strip spacing, steel strip layer number) are discussed. Analysis of bearing capacity of axial compression and development of stress and strain of steel strip. The experimental results show that the axial compressive capacity of reinforced concrete columns strengthened by prestressed steel strips is obviously higher than that of ordinary reinforced concrete columns, and its deformation capacity is enhanced. The test results show that the steel strip spacing has the most significant influence on the bearing capacity. The influence of the number of steel strip layers on the deformation capacity is significant. According to the experimental process, the stress mechanism of reinforced concrete columns strengthened with prestressed steel strip is studied systematically. Based on the experimental data and the theoretical study of confined concrete, the formula of ultimate bearing capacity of reinforced concrete columns strengthened with prestressed steel strips is derived. The results show that the formula is in good agreement with the experimental data. The axial bearing capacity of the members can be calculated accurately. For the convenience of engineering use, the calculation formula for the increase of axial force of steel strip packing and strengthening is given, which can get the increase value of axial compression capacity of strengthened column without considering the reinforcement in column. Through the application of practical strengthening engineering, the prestressed concrete columns with high strength steel strip are packed and strengthened with high strength steel strip, which can improve the bearing capacity of members whose axial compression ratio does not meet the limit value of the code, and can be continued to be used. By comparing the outsourced steel method with the enlarged section method, the results show that the prestressing steel strip packing and strengthening method is the most effective, the cost is low, the construction is simple and suitable for the theoretical checking of the existing engineering reinforcement, and it has good social and economic benefits. It provides theoretical and practical reference for further research and practical engineering application.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU37

【参考文献】