Using the vibration envelope as a damage-sensitive feature in composite beam structures

Abstract

and velocity of the moving load. When compared to shifts in the natural frequencies, it has been verified that the proposed approach generally enjoys a higher sensitivity (so damage can be detected at an early stage), is more effective closer to the ends of the bridge (where shear studs are more likely to be damaged), and displays an ordered set of results (which would reduce the possibility of a false damage). Further work is required to assess the effects of uncertainties and the adoption of more refined models for the moving load.

Monitoring 3D Vibrations in Structures using High‐resolution Blurred Imagery

“…Changes can be observed in the locations of nodes and antinodes, the positions where the amplitude is smallest and largest. In a practical setting, identifying a change in the vibration envelope when one was not expected would trigger further investigation as to the underlying cause, possibly prompting repair work (Kasinos et al., ). Testing was repeated again and results are presented in Fig.…”

“…However, data analysis can be complicated and specialist expertise is necessary to interpret the vibration response. Several approaches exist to identify structural changes from the measured vibration response (Kasinos et al., ). Comparative studies score these approaches on their ability to identify, locate and quantify damage; generally, those approaches which take advantage of a higher number of monitoring points produce the most reliable results (Carden and Fanning, ).…”

Ancillary Computational Tools for the Analysis of Structural Systems

“…They extend, facilitate and simplify the existing capabilities of the SAP2000 OAPI, offering efficiency and readability, thus encouraging future developments for other IDEs. The proposed procedure, aimed at parametric, stochastic and optimisation analysis, provides recommendations to the user and has been successfully employed in our previous investigations on the dynamic analysis of composite beam structures [5] as well as the dynamic analysis of steel frames [4]. It will be demonstrated next through two illustrative examples.…”

“…Figure 6 shows the evolution of the resulting stationary response PDF for t ≥ 1, quantified through the kernel nonparametric probability density esimate, for the two forms of excitation under consideration. 5 10 15 20 −2 The analysis of the three secondary systems under consideration is carried out next. We circumvent the prohibitively time-consuming runs typically encountered in conventional analysis of such strongly-nonlinear systems by exploiting the solvers presented in § 3.…”

“…Finally, the features at the current development stage are showcased on two examples: i) the responsesurface-based reliability analysis of a truss structure facilitated through the use of the SAP2000 OAPI; and ii) the use and interoperability of the standalone solvers developed with SAP2000 for the response quantification of nonlinear cascaded secondary oscillators due to stochastic excitation. Basis of this contribution are the preliminary investigations carried out in [4,5].…”