南京航空航天大学硕士学位论文高强复合玻璃纤维加固钢筋混凝土梁疲劳性能试验研究姓名：张彬申请学位级别：硕士专业：结构工程指导教师：艾军20080301南京航空航天大学硕士学位论文 - i - 摘 要 现有桥梁中有一部分需要进行结构加固，以增强桥梁的承载能力，延长桥梁的使用寿命。本文通过模拟实际桥梁在加固后的疲劳性能，根据 7 根试验梁，对采用高强复合玻璃纤维加固混凝土梁在重复荷载作用下的弯曲性能进行试验研究。主要研究内容与结论如下： 1试验研究表明：粘贴高强复合玻璃纤维后混凝土梁的疲劳寿命增加了 2倍多，其疲劳变形减少了 61%65%，加固梁的疲劳抗裂性能得到了较大改善。因此，粘贴复合玻璃纤维是提高混凝土梁疲劳性能的有效方法，可用于延长混凝土梁的使用寿命。 2本文通过加固梁的钢筋应力幅值与疲劳寿命的关系，拟合出疲劳曲线，并且由疲劳曲线得到了加固梁的疲劳极限值。另外，由加固梁的裂缝最大宽度、裂缝最大长度分别与加载次数的关系，得到了加固梁的裂缝最大宽度与裂缝最大长度的数学模型，从而可进一步研究疲劳荷载水平及加载次数与加固梁的关系。 3由试验数据得出加固梁在疲劳荷载作用下，跨中截面的混凝土应变、钢筋应变以及纤维应变仍能较好地满足平截面假定。同时，结合本次试验数据和相关资料，介绍了混凝土、钢筋和高强复合玻璃纤维等材料的疲劳强度的确定方法。最后，由等效惯性矩法提出了高强复合玻璃纤维加固钢筋混凝土梁的正截面疲劳强度的验算方法。 关键词：关键词：高强复合玻璃纤维，结构加固，钢筋混凝土梁，疲劳荷载，弯曲性能 高强复合玻璃纤维加固钢筋混凝土梁疲劳性能试验研究 - ii - ABSTRACT For improving the loading capability and prolonging the service life, parts of the built bridges need reinforcing. This paper tries to simulate the actual fatigue performance of reinforced bridge. By 7 experiment beams, the research is carried on about the flexural behavior of RC beams reinforced with advanced glass-fiber composites under cyclic loading. The main research contents and conclusions are as follows: 1. By the result of the experiments, it is shown that: The fatigue life of RC beam which is strengthened with advanced glass-fiber composites increases by more than two times, its deflection reduces about 61% to 65% and the fatigue performance of anti-crack has more and greatly improvement. Thus, it has the advantage of improving the fatigue performance of RC beam that is strengthened with advanced glass-fiber composites and prolonging the service life of RC beam. 2. Fatigue curve was fitted by the relationship between stress amplitude of steel bar and fatigue life of RC beams strengthened with advanced glass-fiber composites, and the fatigue limit value of the strengthened RC beam is deduced by the curve. In addition, by the relationship between the max crack length of strengthened RC beam and the loading cycles, and the relationship between the max crack width of strengthened RC beam and the loading cycles, the mathematical models are founded. By this, it can be studied further more about the effect of the repeated loading level and loading cycles to the strengthened RC beam. 3. According to the statistics result from experiments, the strains of concrete, steel bar and fiber of the strengthened RC beams at the mid-span almost remain linear under fatigue loading. In the meantime, the method for gaining the fatigue strength of concrete, steel bar and advanced glass-fiber composites is drawn from the conclusions of the experiments. At the end, by the method of equivalent inertial moment, a checking method is brought up about the fatigue strength of the cross-section of RC beam strengthened with advanced glass-fiber composites. Key Words: advanced glass-fiber composites，strengthening，RC beam， fatigue loading，flexural behavior 高强复合玻璃纤维加固钢筋混凝土梁疲劳性能试验研究 - vi - 图表清单 图 1.1 FRP 在交通和建筑工程中的应用.6 图 2.1 梁的配筋图.12 图 2.2 纤维粘贴图.12 图 2.3 加固后的钢筋混凝土梁.14 图 2.4 计算简图.18 图 2.5 DH3817 动静态应变测试系统.18 图 2.6 试验加载装置图.19 图 2.7 试验加载装置实图.19 图 2.8 疲劳试验加载程序.22 图 2.9 测试点布置图.22 图 3.1 钢筋疲劳断裂.25 图 3.2 纤维剥落.25 图 3.3 加固 RC 梁的 S-N 曲线.26 图 3.4 梁 LJP-1 跨中截面应变分布图 .27 图 3.5 梁 LJP-2 跨中截面应变分布图 .27 图 3.6 梁 LJP-3 跨中截面应变分布图 .27 图 3.7 梁 LJP-4 跨中截面应变分布图 .27 图 3.8 钢筋应变与加载次数的关系曲线.28 图 3.9 混凝土应变与加载次数的关系曲线.28 图 3.10 钢筋应变与加载次数的关系曲线（梁 LJP-1） .29 图 3.11 混凝土应变与加载次数的关系曲线（梁 LJP-1）.29 图 3.12 纤维应变与加载次数的关系曲线（梁 LJP-1） .