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Full-Text Articles in Engineering
System Identification Of Base-Isolated Building Using Seismic Response Data, T. Furukawa, M. Ito, K. Izawa, Mohammad N. Noori
System Identification Of Base-Isolated Building Using Seismic Response Data, T. Furukawa, M. Ito, K. Izawa, Mohammad N. Noori
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Due to the complex nature of the excitation, and the inherent dynamics characteristics of restoring force of the base isolation systems, the response of base-isolated structures subject to strong earthquakes often experiences excursion into the inelastic range. Therefore, in designing base-isolated structures, the nonlinear hysteretic restoring force model of the base isolation system is frequently used to predict structural response and to evaluate structural safety. In this paper, the prediction error method system identification technique is used in conjunction with nonlinear state-space models for identification of a base-isolated structure. Using a variety of nonlinear restoring force models and bidirectional recorded …
Structural Health Monitoring And Damage Detection Using An Intelligent Parameter Varying (Ipv) Technique, Soheil Saadat, Mohammad N. Noori, Gregory D. Buckner, Tadatoshi Furukawa, Yoshiyuki Suzuki
Structural Health Monitoring And Damage Detection Using An Intelligent Parameter Varying (Ipv) Technique, Soheil Saadat, Mohammad N. Noori, Gregory D. Buckner, Tadatoshi Furukawa, Yoshiyuki Suzuki
Office of the Dean (CENG) Scholarship
Most structural health monitoring and damage detection strategies utilize dynamic response information to identify the existence, location, and magnitude of damage. Traditional model-based techniques seek to identify parametric changes in a linear dynamic model, while non-model-based techniques focus on changes in the temporal and frequency characteristics of the system response. Because restoring forces in base-excited structures can exhibit highly non-linear characteristics, non-linear model-based approaches may be better suited for reliable health monitoring and damage detection. This paper presents the application of a novel intelligent parameter varying (IPV) modeling and system identification technique, developed by the authors, to detect damage in …
Wavelet-Based Approach For Structural Damage Detection, Z. Hou, Mohammad N. Noori, R. St. Amand
Wavelet-Based Approach For Structural Damage Detection, Z. Hou, Mohammad N. Noori, R. St. Amand
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A wavelet-based approach is proposed for structural damage detection and health monitoring. Characteristics of representative vibration signals under the wavelet transformation are examined. The methodology is then applied to simulation data generated from a simple structural model subjected to a harmonic excitation. The model consists of multiple breakable springs, some of which may suffer irreversible damage when the response exceeds a threshold value or the number of cycles of motion is accumulated beyond their fatigue life. In cases of either abrupt or accumulative damages, occurrence of damage and the moment when it occurs can be clearly determined in the details …
Random Vibration Studies Of An Sdof System With Shape Memory Restoring Force, L. Duval, Mohammad N. Noori, Z. Hou, H. Davoodi, S. Seelecke
Random Vibration Studies Of An Sdof System With Shape Memory Restoring Force, L. Duval, Mohammad N. Noori, Z. Hou, H. Davoodi, S. Seelecke
Office of the Dean (CENG) Scholarship
Intelligent and adaptive material systems and structures have become very important in engineering applications. The basic characteristic of these systems is the ability to adapt to the environmental conditions. A new class of materials with promising applications in structural and mechanical systems is shape memory alloy (SMA). The mechanical behavior of shape memory alloys in particular shows a strong dependence on temperature. This property provides opportunities for the utilization of SMAs in actuators or energy dissipation devices. However, the behavior of systems containing shape memory components under random excitation has not yet been addressed in the literature. Such a study …
Stability And Performance Of Feedback Control Systems With Time Delays, M. S. Ali, Z. K. Hou, Mohammad N. Noori
Stability And Performance Of Feedback Control Systems With Time Delays, M. S. Ali, Z. K. Hou, Mohammad N. Noori
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This paper investigates the time delay effects on the stability and performance of active feedback control systems for engineering structures. A computer algorithm is developed for stability analysis of a SDOF system with unequal delay time pair in the velocity and displacement feedback loops. It is found that there may exist multiple stable regions in the plane of the time delay pair, which contain time delays greater than the maximum allowable values obtained by previous studies. The size, shape and location of these stable and unstable regions depend on the system parameters and the feedback control gains. For systems with …