Key Engineering Materials Vol. 662

Abstract: Mechanical tests of samples of basalt and textile glass reinforcement were performed within the solution of the research project GAČR 13-12676S and SGS14/171/OHK1/2T/31. These tests were carried out because of the need to establish elementary mechanical quantities that are tensile strength and modulus of elasticity of non-conventional reinforcement. Both of these quantities are required for further modeling of structures and for designing of the elements made from textile reinforced concrete (TRC) as not being provided by reinforcement manufacturers. The tests were carried out on a total of 12 samples of reinforcement where the first 6 samples were made from textile glass reinforcement (AR-G = Alkali-Resistant Glass) and the remaining 6 samples were prepared from basalt reinforcement. The filament sheaf fibers called roving was used for the production of test specimens.

Abstract: In contrast to imaging in visible spectrum temporally-varying distortion (drift distortion) caused by positional errors of electron beam during the scanning process occurs in SEM devices. This effect is always present in the data from SEM and its magnitude depends on acquisition time, magnification and conductivity of the sample (where lower conductivity causes higher drift distortion). In this paper 2D digital image correlation based on Lucas-Kanade algorithm was used to assess drift distortion characteristics of MIRA II LMU SEM device during imaging of materials with different conductivity and microstructural properties. Using the DIC technique deformations in the micrographs were evaluated and tool for correction of positional errors was developed. As shown on a set of selected multiphase mixtures this tool enables qualitative backscattered electron analysis independently on the material type and imaging parameters including acquisition time. This enables reliable evaluation of material parameters that have influence on effective mechanical properties.

Abstract: Short survey of the literature revealed that the addition of nanoparticles, e.g., nano- SiO₂, Al₂O₂, CuO, TiO₂, ZnO₂, Fe₂O₃, Cr₂O₃ in concrete result in improvement of its physical and mechanical properties.

Abstract: The aim of this article is to demonstrate to what extent there is an impact on the micromechanical properties of a standardized testing sample made of rubber compound based on synthetic rubber EPDM and produced by injection molding in comparison with a sample produced by classic preparation (cutting off a compression molded plate). Measurement of the properties was carried out according to the instrumented test (DSI), in compliance with ISO 14577 on the measuring device micro-combi-tester.