Progressive damage tests

Ambient vibration testing Data normalization Progressive damage testing Structural health monitoring System identification... 

The ambient, shaker, and drop weight data from scenario 8 of the progressive damage test have been employed as benchmark data for system identification methods for operational modal analysis. Peeters and Ventura (2003) compare the modal parameter estimates obtained by seven different research teams in the framework of this benchmark. In addition, new modal parameter estimation techniques have been validated on the benchmark data. The best reported result was obtained by applying a subspace identification algorithm (Reynders and De Roeck 2008) and a maximum likelihood algorithm... 

Modal characteristics cannot only be used for monitoring and damage detection but also for damage localization and quantification. The progressive damage test data from the Z24 bridge have served as benchmark data in this context, and Reynders and De Roeck (2009) present a... 

The paper is presented in three parts. First, the tests employed to determine the mixed mode fracture envelope of a glass fibre reinforced epoxy composite adhesively bonded with either a brittle or a ductile adhesive are briefly described. These include mode I (DCB), and mixed mode (MMB) with various mixed mode (I/II) ratios. In the second part of the paper different structural joints will be discussed. These include single and double lap shear and L-specimens. In a recent European thematic network lap shear and double lap shear composite joints were tested, and predictions of failure load were made by different academic and industrial partners [9,10]. It was apparent that considerable differences existed between different analytical predictions and FE analyses, and correlation with tests proved complex. In particular, the progressive damage development in assemblies bonded with a ductile adhesive was not treated adequately. A more detailed study of damage mechanisms was therefore undertaken, using image analysis combined with microscopy to examine the crack tip strain fields and measure adherend displacements. This is described below and correlation is made between predicted displacements and failure loads, based on the mixed mode envelope determined previously, and measured values. 

Figure 16.42 Comparison of normalized progressive damage accumulation as a function of the fraction of life of the tested specimens [99].

The major factor in skin diseases caused by exogenous substances is the repeated and cumulative action on the skin of agents in weak irritant solutions. The repeated exposure to surfactants represents a model for the induction of ICD (Tupker et al. 1989a). During the course of the exposure (patch test applied twice daily for 3 weeks), a progressively damaging clinical effect accompanied by an increase in TEWL (due to a cumulative action of these agents on the skin) is observable. 

RESULTS FROM IN-REACTOR SEVERE FUEL DAMAGE TESTS THAT USED FULL-LENGTH FUEL RODS AND THE RELEVANCY TO LWR SEVERE ACCIDENT MELT PROGRESSION SAFETY ISSUES... 

Kada, T. (1981) The DNA-damaging activity in 42 coded componnds in the rec-assay. In de Serres, F.J. Ashby, J., eds. Progress in Mutation Research, Voinme I, Evaluation of Short-Term Tests for Carcinogens. Report of the International Collaborative Program, Amsterdam, Elsevier Science, pp. 175-182... 

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