This paper describes a comparison, both analytically and experimentally, between two widely used loss factor estimation techniques frequently used in statistical energy analysis. Analytical models of simple spring/mass/damper systems were created to compare frequency-averaged loss factor values from the single subsystem power injection method and the impulse response decay method. The parameter...

This paper studies the solution behavior of a system of two coupled elastic beams connected vertically by springs. With the viscous damping collocated with the ends of the springs, the system energy decays exponentially. Our goal is to find the optimal spring-damper location which yields the best energy decay rate of the beam-spring system.

In this work, three types of vehicle suspensions were considered and modeled as follows: oil damper mounted in parallel with a compression helical spring, for which a Kelvin-Voigt model, consisted of a dashpot and an elastic element connected in parallel is considered; colloidal damper without attached compression helical spring, for which a Maxwell model, consisted of a dashpot and an elastic ...

In this paper, numerical aspects of a sensitivity control for the semi-active suspension system with a magneto-rheological (MR) damper are investigated. A 2-dof quarter-car model together with a 6th order polynomial model for the MR damper are considered. For the purpose of suppressing the vertical acceleration of the sprung mass, the square of the vertical acceleration is defined as a cost fun...

The most important property of a base-isolation system is to make the base more flexible than the elements of the superstructure, but it must still be stiff enough to resist typical pounding forces, wind loadings, and similar low-amplitude horizontal forces. However, the potential consequences of earthquake-induced poundings on seismically isolated buildings can be much more substantial, and, t...

The high cost of experimentation has long put a damper on companies' attempts to create great new products. But new technologies are making it easier than ever to conduct complex experiments quickly and cheaply. Companies now have an opportunity to take innovation to a whole new level--if they're willing to rethink their R&D from the ground up.

A suspended ceiling system (SCS) is one of the most fragile and non-structural elements during earthquakes. However, effective seismic protection technologies for enhancing have not been developed other than steel bracing system. An innovative passive vibration control proposed in this paper, which equipped a damper-employed pulley amplification mechanism into indirect system, named pulley–damp...

This paper presents an efficient control strategy for magnetorheological (MR) dampers embedded in building structures to mitigate quake-induced vibrations. In this work, MR dampers are used as semi-active devices, taking the advantages of the fail-safe operation and low power requirement. By using a static hysteresis model for the MR damper, a suitable controller is proposed here for direct con...

This paper presents the evaluation of seismic performance and cost-effectiveness of a multiple slim-type damper system developed for the vibration control of earthquake excited buildings. The multiple slim-type damper (MSD) that consists of several small slim-type dampers and linkage units can control damping capacity easily by changing the number of small dampers. To evaluate the performance o...