The influence of concrete inhomogeneity on elastic response of the sample under dynamic load
Journal Title: Bulletin of the Military University of Technology - Year 2016, Vol 65, Issue 4
Abstract
Results of the dynamic loading analysis of the heterogeneous concrete rectangular samples are presented in the article. This heterogeneity is set randomly with respect to the basic mechanical parameters: the mass density and the modules of concrete deformation. These both parameters define the elastic wave velocities. According to experimental researches by the ultrasounds method, the values of the longitudinal wave velocity is between (3,0 ÷ 5,0) [km/s]. By the draw of the randomly mechanical parameters this interval was kept. The rating of the heterogeneity is expressed in terms of concrete strength using a dependence correlation between the phase velocity and an average local strength of concrete. The results of numerical analysis of wave reaction of rectangular concrete samples were obtained by the differential discretization, which evolved the sample into a three-dimensional model of the type of a discreet structural quasi-mesosystem. It is shown that the excessive heterogeneity revealed the initiation of unstable deformation processes.[b]Keywords:[/b] differential approximation, explicit integration scheme, spatial analysis of the wave
Authors and Affiliations
Robert Osiński, Grzegorz Bąk
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