A dynamic method for mass detection, considering attaching positions of micro-objects on microcantilevers, is introduced. Two models based on the Rayleigh– Ritz method were developed for analyses of the first flexural and the first torsional modes of a “cantilever– mass” system, respectively. Due to one-to-one correspondence between the longitudinal adhering positions of the micro-objects and t...

Typically, beams that form part of structural systems are subjected to vertical distributed loading along their length. Distributed loading affects moment and shear distribution, and consequently spread of inelasticity, along the beam length. However, the finite element models developed so far for seismic analysis of frame structures either ignore the effect of vertical distributed loading on s...

The recently developed drift spectrum is extended to buildings that do not deform laterally like pure shear beams. Similarly to Iwan’s drift spectrum, the proposed generalized interstory drift spectrum uses a continuous linear-elastic model to obtain estimates of interstory drift demands in buildings. However, the generalized interstory drift spectrum is based on a continuous model that consist...

This paper deals with the experimental and numerical assessment of the vibration suppression of smart structures using piezoelectric shear actuators. Experimental results are presented for an adaptive sandwich cantilever beam that consists of aluminum facings and a core made of two piezoelectric shear actuators and foam. The electric Þeld is applied perpendicular to the poling direction of the ...

The influence of the beam geometry on the quality factor and resonance frequency of resonant silicon cantilever beams vibrating in their fundamental in-plane flexural mode in water has been investigated. Compared to cantilevers vibrating in their first out-of-plane flexural mode, utilizing the in-plane mode results in reduced damping and reduced mass loading by the surrounding fluid. Quality fa...

ABSTRACT Blade failure is a common problem of a steam turbine and it’s failure in-service results in safety risks, repair cost and non operational revenue losses. Thus, the reliability of these blades is very important for the successful operation of a steam turbine. Dynamic analysis of a steam turbine blade in computational environment is carried out in the present work. In order to gain physi...

in this paper, nonlinear vibration and instability response of an embedded pipe conveying viscose fluid is investigated. the pipe is considered as a timoshenko beam embedded on an elastic foundation which is simulated by spring constant of the winkler-model and the shear constant of the pasternak-model. the external flow force, acting on the beam in the direction of the flexural displacement is...

We present a systematic investigation of the dynamic properties of silicon nitride cantilevers in air. The thermal noise spectra of cantilevers have been measured using a home-made optical deflection setup. Torsional and flexural resonances up to the seventh mode are observed. The dependence of resonance frequencies on the dimensions and mode number is studied in detail. It is found that underc...

the static pull-in instability of beam-type micro-electromechanical systems is theoretically investigated. two engineering cases including cantilever and double cantilever micro-beam are considered. considering the mid-plane stretching as the source of the nonlinearity in the beam behavior, a nonlinear size-dependent euler-bernoulli beam model is used based on a modified couple stress theory, c...