Materials Science Forum Vol. 952

Abstract: The paper deals with the modeling of the technological texture of the pressed ceramic materials in the radial and axial direction, which consists in the graphical representation and subsequent analysis of the distribution of the electrostatic field potential differences on the surface of the dielectric sample with the diameter d and the thickness h located between the electrodes. In occasion of observing radial texture the electrodes have the cylindrical configuration and in occasion of observing the axial texture in the sample the electrodes have the axial configuration. The theoretical relationship in the paper is derived for the calculation of the voltage values measured at any position between the center electrode and the peripheral electrode, at a constant voltage U applied to the outer and inner electrodes of the dielectric sample of thickness h of the raw ceramic sample material (radial texture). Measurements have demonstrated the suitability of identifying the technological texture by measuring the potential differences on the sample surface which is located between the electrodes in the relation to the technology preparation and to the quality of the fired ceramic production.

Abstract: To obtain high-quality concrete constructions it is not enough to execute it only in concrete of high class. One of the effective ways to improve the reliability and durability of concrete is its reinforcing by various kinds of fibers. The article presents the researching results of the influence of brands of portland cement and disperse reinforcing by polyethylene terephthalate fibers (PET-fiber) on concrete durability. Standard compression tests of the cubical prototypes of fine-grained sand concrete made of two brands of portland cement – PC400 and PC500 with different percentage of PET-fibers have been conducted. The optimum content of PET-fiber, wherein there is a maximum increase of durability of fine-grained fiber-reinforced concrete, has been set.