This paper presents results of an experimental study that focuses on monitoring changes in dynamic characteristics of a damaged and retrofitted two-story reinforced concrete (RC) building model with poor detailing. In the study, ambient vibration tests are performed via four test setup protocols in order to monitor changes in dynamic characteristics before and after such setups. The four main test setups are: (i) undamaged (as-built) case (Setup # 1), (ii) damaged cases with different degrees of damages (Setup # 2), (iii) repaired case with different types of repair methods (Setup # 3), and (iv) strengthened case with externally bonded CFRP composite laminates (Setup # 4). In addition, a total of eight ambient vibration tests are conducted in order to assess the effects of degree of damage and associated retrofit systems on building’s dynamic characteristics such as natural frequencies, mode shapes, and damping ratios. The Stochastic Subspace Identification (SSI) Method is used to identify the dynamic characteristics. Experimentally identified dynamic characteristics obtained from all setups are compared with each other in order to detect the effect of damage and repair applications on the structure’s dynamic characteristics. Moreover, Modal Assurance Criterion (MAC) and Coordinate Modal Assurance Criterion (COMAC) are determined to examine the changes of stiffness of each RC building model.

本文介绍了一项实验研究的结果，该研究侧重于监测细节不佳的受损和翻新的两层钢筋混凝土 (RC) 建筑模型的动态特性变化。在研究中，环境振动测试通过四种测试设置协议进行，以监测此类设置前后动态特性的变化。四个主要的测试设置是：（i）未损坏（竣工）案例（设置#1），（ii）不同程度损坏的损坏案例（设置#2），（iii）使用不同类型修复方法的修复案例（设置#3），和（iv）使用外部粘合的CFRP复合层压板加固外壳（设置#4）。此外，总共进行了八次环境振动测试，以评估损坏程度和相关改造系统对建筑物动态特性（如固有频率、振型和阻尼比）的影响。随机子空间识别（SSI）方法用于识别动态特性。从所有设置中获得的实验确定的动态特性相互比较，以检测损坏和修复应用程序对结构动态特性的影响。此外，确定模态保证准则（MAC）和坐标模态保证准则（COMAC）来检查每个RC建筑模型的刚度变化。随机子空间识别（SSI）方法用于识别动态特性。从所有设置中获得的实验确定的动态特性相互比较，以检测损坏和修复应用程序对结构动态特性的影响。此外，确定模态保证准则（MAC）和坐标模态保证准则（COMAC）来检查每个RC建筑模型的刚度变化。随机子空间识别（SSI）方法用于识别动态特性。从所有设置中获得的实验确定的动态特性相互比较，以检测损坏和修复应用程序对结构动态特性的影响。此外，确定模态保证准则（MAC）和坐标模态保证准则（COMAC）来检查每个RC建筑模型的刚度变化。