Methods for damage localization, based on modal parameters, are validated by means of numerical examples and experiments. In this paper, different load and damage cases are simulated with a Finite-Element model of a prestressed reinforced concrete bridge. Taking nonlinear material behaviour into account, realistic crack propagations and decrease of stiffness can be detected. The damage is local...

Determination and analysis of vibration behavior of structures for at least first few natural frequencies and mode shapes needs several sensors to be connected at different non node points and exciting the structure at one point. Other method for determination of first few mode shapes is to excite several points of the structure at once and sensing the response from one point.  Both methods nee...

During the advent of active structural acoustic control, attempts were made to target and control structural vibration mode shapes to reduce radiated sound power. In the late eighties and early nineties work on acoustic radiation mode shapes developed an alternative way to target structural acoustic radiation. By attempting to control the radiation mode shapes, contributing structural modes cou...

Mode shapes are sensitive to the structural condition of bridges but a reasonable estimate such changes require several accelerometers, which can be resource intensive. This paper obviates this problem through novel structure health monitoring (SHM) approach for estimating modal parameters bridges, including damage-induced boundary conditions by using progressively re-deploying sensors along mo...

Reciprocating diaphragm micro-pumps are the most common type among indirectly–driven micro-pumps. They operate by reciprocating the diaphragm with associated check valves. This paper addresses the Hydroelastic vibration of circular elastic diaphragm interacting with the incompressible and inviscid liquid inside the cylindrical chamber with a central discharge opening. Taking into account axisym...

Abstract In recent years, there has been a surge of interest in modal-based monitoring systems, especially for bridge structures, to detect damage at an early stage and extend the life existing bridges as well minimize maintenance costs. The modal parameters, natural frequencies mode shapes, depend on stiffness mass structure. For economic application system, estimation parameters based Operati...

In this paper, full scale load test of a horizontally curved steel box-girder bridge is carried out in order to detect structural defects, which reportedly result in unwanted vibrations in nearby buildings. The bridge is tested under the passage of six heavy vehicles at different speeds, so as to determine its static and dynamic responses. A total number of one hundred and two (102) sensors are...

This paper presents the experimental and analytical modal analysis of a concrete-filled (CFT) tube half-through arch bridge, with the span length of 90m, located at the center of Xining City, Qinghai province, China. Dynamic field test was carried out just prior to the official opening of bridge in order to inspect the dynamic characteristics of the bridge and make a baseline record for the fut...