内压作用下预应力纤维布补强钢管试验及理论分析

发布时间：2019-02-08 21:27

【摘要】：纤维材料被广泛应用于工程的修复加固领域,其中预应力FRP用于修补缺陷压力钢管不仅能有效增大压力钢管的承载能力,提高纤维材料的使用效率,解决FRP的应力滞后现象,还可以避免停车作业所带来的经济损失。文章以自行设计开发的预应力锚具一体式装置为主线,分别研究该装置应用于工程实践中涉及到的四个核心问题,分别是:胶粘剂涂抹位置和胶粘剂凝结固化之后,卸载该装置对补强效果的影响、胶粘剂抗剪性能和建立纤维布补强压力钢管应施加预应力的计算式。首先通过静水压力试验分析对比两种涂抹胶粘剂的位置即在纤维布表面涂抹和在钢管表面涂抹,研究其对纤维布粘结效果的影响。从而选择更适合施工的胶粘剂涂抹方式。还分析了在胶黏剂凝结固化之后卸载预应力锚具施加装置,对比压力钢管前后承载力变化幅度,结果表明卸载预应力施加装置后钢管承载能力变化幅度较小,实际施工最后可卸载装置,实现装置的循环利用,降低维护费用。接着以剩余承载力理论为基础,并结合由试验拟合得出的纤维布应变与预应力之间的关系式及经典管道力学理论,建立出对于不同缺陷下修补压力钢管应施加的预应力的计算式。最后,对于加固体系而言胶粘剂的择取直接影响着补强效果。论文由已知的纤维布与钢材之间的剪切滑移曲线,结合试验数据,最终通过积分求解的方式得出结构胶应具有的抗剪性能的计算式,为工程实践中选择结构胶的种类提供一定的参考。
[Abstract]:Fiber materials are widely used in the field of repair and reinforcement of engineering, in which prestressed FRP can not only effectively increase the bearing capacity, improve the efficiency of fiber materials, and solve the stress lag phenomenon of FRP, but also can effectively increase the bearing capacity of penstock, improve the use efficiency of fiber materials, and solve the problem of stress lag of FRP. It can also avoid the economic loss caused by parking operation. Taking the integrated device of prestressed Anchorage designed and developed by ourselves as the main line, this paper studies the four core problems involved in the application of the device in engineering practice, namely, the position of adhesive smear and the solidification of adhesive. The effect of unloading device on reinforcing effect, shear resistance of adhesive and calculation formula of prestressing force applied to fiber reinforced steel tube are established. Firstly, through hydrostatic pressure test, the position of two kinds of coating adhesive, that is, on the surface of fiber cloth and on the surface of steel pipe, was analyzed and compared, and the effect of the two kinds of adhesive on the adhesive effect of fiber cloth was studied. In order to choose more suitable for the construction of adhesive smear mode. The loading capacity of unloaded prestressed Anchorage is also analyzed after the adhesive is solidified. The results show that the load capacity of the steel tube after unloading the prestressing force is smaller than that of the steel tube before and after the pressure pipe is loaded. Finally, the actual construction can be unloaded to realize the recycling of the device and reduce the maintenance cost. Then based on the theory of residual bearing capacity and combined with the relationship between fiber cloth strain and prestressing force obtained from the experiment and the classical pipe mechanics theory, The formula of prestressing force applied to repair penstock with different defects is established. Finally, for the reinforcement system, the choice of adhesive directly affects the reinforcement effect. Based on the known shear slip curve between fiber cloth and steel, and the experimental data, the formula of shear resistance of structural adhesive is obtained by integral solution. It provides a certain reference for the selection of structural adhesives in engineering practice.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE973

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