【摘要】 在对碳纤维布加固锈蚀钢筋混凝土梁进行四点弯曲疲劳试验的基础上,研究了加固梁抗弯刚度和损伤变量、荷载加载次数与疲劳寿命比之间的关系。试验结果表明:加固梁抗弯刚度的衰减曲线包括初始的快速减小阶段、稳定衰减阶段和梁临近破坏的快速减小阶段。分析结果表明:加固梁的线性刚度比介于0.6~0.9之间,平均值为0.75,破坏刚度比介于0.4~0.8之间,平均值为0.6,加固梁疲劳破坏时损伤变量约为0.4,此值可作为碳纤维布加固锈蚀钢筋混凝土梁疲劳破坏的失效判据。更多还原

【Abstract】 The fatigue tests of four corroded reinforced concrete(RC) beams strengthened with carbon fiber composite sheets were carried out to investigate the relationships between the bending stiffness and such parameters as the damage variable,the ratio between the cyclic number of fatigue loading and the fatigue life.The results show that the degradation curve of bending stiffness includes a rapid decay phase,a uniform decay phase,and a rapid decay phase close to the failure.It is found that the normalized linear stiffness varies from 0.6 to 0.9,with a mean value of 0.75,and the normalized fracture stiffness varies from 0.4 to 0.8,with a mean value of 0.6.The damage variable of the strengthened beams reaches about 0.4 at the fatigue failure point and it can be taken as fatigue failure criterion of corroded RC beams strengthened with carbon fiber composite sheets.更多还原