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Effective telematics application of wireless and fiber bragg grating sensors for structural health monitoring of tall buildings

Saidov K., Szpytko J.

Archives of Transport System Telematics

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2015

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Vol. 8, iss. 3

35--40

EN

In recent years, there has been an increasing interest in the adoption of emerging sensing technologies for instrumentation within a variety of structural systems in civil and building engineering. Wireless and fiber bragg grating sensors are emerging as sensing paradigms that the structural engineering field has begun to consider as substitutes for traditional tethered monitoring systems. A benefit of each sensors structural monitoring systems is that they are inexpensive to install because extensive wiring is no longer required between sensors and the data acquisition system. Researchers has been discovering that wireless and fibber bragg grating sensors are an exciting technology that should not be viewed as simply a substitute for traditional tethered monitoring systems. Rather, these sensors can play greater roles in the processing of structural response data; this feature can be utilized to screen data for signs of structural damage. Also, sensors have limitations that require novel system architectures and modes of operation. This paper is intended to present a summary review of the collective experience the structural engineering community has gained from the use of wireless and fiber bragg grating sensors for monitoring structural performance and health of tall type buildings.

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Kinematically excited parametric vibration of a tall building model with a TMD - Part 2: Experimental analyses

Majcher K., Wójcicki Z., Grosel J., Pakos W., Sawicki W.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 1

218--229

EN

This paper constitutes the second part of the article Kinematically excited parametric vibration of a tall building model with a TMD. Part 1: numerical analyses (ACME, in press) by K. Majcher and Z. Wójcicki, which presents the results of theoretical research. This paper presents the experimental verification of those results. The experimental studies were carried out with the use of an especially designed physical model of a tall building, which rested on an earthquake simulator – a shaking table – created for this project. The simulator was used to generate several types of kinematic excitations: harmonic ones, superpositions of harmonic ones and, finally, ones generated on the basis of real seismograms. Vibrations were kinematically excited in the horizontal and vertical directions independently and simultaneously. The vertical component of the earthquake causes the pendulum suspension point to vibrate, thus exciting the pendulum parametrically. The theoretical study indicated a significant influence of this parametric excitation (parametric resonance) on the effectiveness of the Pendulum Tuned Mass Damper (PTMD). Therefore, the experimental analyses were especially focused on the parametric effects' impact on: the PTMD's ability to reduce the building's vibration, and the possibility of parametric resonance of the building due to parametric resonance of the PTMD.

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Kinematically excited parametric vibration of a tall building model with a TMD - Part 1: Numerical analyses

Majcher K., Wójcicki Z.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 1

204--217

EN

This paper undertakes to analyze the research problem of vibration of a tall building with a Pendulum Tuned Mass Damper (PTMD). The vibration of the building-damper system is due to kinematic excitation representing seismic load. It was assumed that during an earthquake the ground can move horizontally and vertically. An analysis of various earthquakes reveals that, sometimes, the vibration has comparable amplitudes in both these directions. It is usually the horizontal vibration that is catastrophic to structures. Vertical vibration is therefore often omitted. As this paper will show, in cases where the TMD model is a pendulum, the vertical ground motion can be transmitted through the building structure to the pendulum suspension point. In such cases, parametric resonance may occur in the system, which is especially dangerous as it amplifies vibration despite the presence of damping. Taking this phenomenon into consideration will make it possible to better secure the structure against earthquakes. As the teams carrying out theoretical and experimental analyses differed, the paper was purposely divided into two parts. In the first part, the idea was formulated and the MES model of the building-TMD system was created. The second part contains an experimental verification of the theoretical analyses.