In this study, a new approach for global/local damage detection in a finite element model of structures, with limited sensors, is proposed using identified system Markov parameters. The proposed damage detection is directly related to the Markov parameters, locations of actuators and sensors. Also there is no explicit relation between DDA/ISMP and mode shapes. So, it is unnecessary to install a sensor at each DOF for measuring output to identify mode shapes unlike the other damage detection techniques in which mode shapes play an important role in damage identification. The stiffness of all elements of a structure is identified using the proposed DDA/ISMP. The effects of noise, numbers and locations of sensors on the identification precision are investigated. The results demonstrate that, with the limited sensors and the noise contamination in the measured responses, the DDA/ISMP can effectively identify the locations, types and quantities of damages, both locally and globally. To illustrate the efficiency of DDA/ISMP, a four-storey steel moment frame structure and a five-storey shear building are used. Our numerical results show that the DDA/ISMP technique in damage detection is more effective than the scheme proposed by Xu et al. Also, the time consumed in DDA/ISMP is considerably less than the method introduced by Xu.

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Damage detection in large building structures has always faced challenges due to analyzing the large amount of measured data. In this article, a new damage detection approach based on subspace method is proposed to identify damages using limited output data. Also, a new scheme is presented to develop a smart structure by integrating structural health monitoring with semi-active control strategy. If damage occurs in such a structure under severe excitations, the proposed scheme has the capability to exert necessary control forces in order to compensate for damage and reduce simultaneously the dynamic response of the structure. The reliability and feasibility of the proposed method are demonstrated by implementing the technique to two shear building structures with semi-active control devices. Results show that the damage could be identified accurately with saving time and cost due to less computation even under noise existence; and dynamic response is significantly reduced in the smart structure.

Integrated structural health monitoring (SHM) and vibration control has been considered recently by researchers. Up to now, all of the research in the field of integrated SHM and vibration control has been conducted using control devices and control algorithms to enhance system identification and damage detection. In this study, online SHM is used to improve the performance of structural vibration control, unlike previous research. Also, a proposed algorithm including integrated online SHM and a semi-active control strategy is used to reduce both damage and seismic response of the main structure due to strong seismic disturbance. In the proposed algorithm the nonlinear behavior of the building structure is simulated during the excitation. Then, using the measured data and the damage detection algorithm based on identified system Markov parameters (DDA/ISMP), a method proposed by the authors, damage corresponding to axial and bending stiffness of all structural elements is identified. In this study, a 20 t MR damper is employed as a control device to mitigate both damage and dynamic response of the building structure. Also, the interaction between SHM and a semi-active control strategy is assessed. To illustrate the efficiency of the proposed algorithm, a two bay two story steel braced frame structure is used. By defining the damage index and damage rate index, the input current of the MR damper is generated using a fuzzy logic controller. The obtained results show that the possibility of smart building creation is provided using the proposed algorithm. In comparison to the widely used strategy of only vibration control, it is shown that the proposed algorithm is more effective. Furthermore, in the proposed algorithm, the total consumed current intensity and generated control forces are considerably less than for the strategy of only vibration control.

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