Nested Hierarchical Design Application in Production of Ceramic Glazed Floor Tiles

The challenges of using locally available materials in Nigeria to meet the tiles demand that will be affordable and compete favourably with imported products will no doubt not only contribute to our Gross Domestic Product but also meet the yearning of the Federal Government on her local content policy. This necessitated this study to aim at the production of ceramic floor tiles with clays modified with naturally occurring materials. An experimental method was adopted to carry out this research work. Different clay samples were purposively gotten from Mbaukwu town, Anambra State, Nigeria. Rice husk, silt, feldspar, quartz was obtained to serve as modifiers. An elaborate nested experimental design, structured as an analytical hierarchy process, and festooned with three base materials, 4-modifiers, and with replications, facilitated the achievement of the production. The nested design was developed to guide in the optimum combination of materials that will give the best yield of tiles. The base materials were used in combination with the four modifiers at different percentage levels. The tiles produced were subjected to same test in order to ascertain their behavior in terms of weather, resistance to abrasion, compatibility with mortar, water absorption, dilute acid, Sodium Hydroxide and detergent. The experimental tiles produced compete favorably with any foreign product as it was seen to match up with “Vetrified tiles” and “Gomex tile” from Italy and satisfies NIS 427: 2000. Glazed ceramic floor tiles have been successfully manufactured locally using clay and other naturally occurring materials and it has given excellent performance characteristics.

Effect of pedestrian traffic on the slip resistance and visual appearance of ceramic floor tiles

The increase of surface roughness is a common measure for improving the slip resistance of floors. Nevertheless, the surface roughness of the floors can wear out during the use. Furthermore, rough surfaces can be susceptible to dirt accumulation. As a consequence, during the use, the original slip resistance and visual appearance of the floors can be deteriorated. In this scenario, the objective of this work was to evaluate the effects of pedestrian traffic on the surface profile, slip resistance and visual appearance of commercial ceramic floor tiles. The surface profile (contact profilometer), slip resistance (pendulum method) and visual appearance (visual analysis) of different commercial ceramic floors were evaluated before and after their exposure to heavy pedestrian traffic, and the results were compared. Significant reductions of the sharpness and height of profile peaks of the surfaces, due to mechanical wear, were observed. Consequently, for all the surfaces which initially presented satisfactory slip resistance for use in slipping risk areas, this property was reduced to unsafe levels. The degree of dirt accumulation, and the consequent visual appearance deterioration, varied according to the profile characteristics of the studied floors. The best cleaning performances were found for surfaces with more spaced irregularities and wider profile valleys.

Correlations between the slip resistance and surface roughness of ceramic floor tiles

The characteristics of the floor surface profile are one of the factors that can be responsible for slip and fall accidents. To reduce the incidence of these accidents, it is essential to identify the profile features necessary for floor covering materials to be suitable for slipping risk areas. The objective of the present work was to investigate correlations between the slip resistance and the surface roughness of ceramic floor tiles. The slip resistance and the surface roughness of commercial ceramic tiles, with a diversity of surface finishes, were characterized by the pendulum method and contact profilometry, respectively. It was concluded that the presence of a large number of sharp peaks per unit of length of the profile is required for high slip resistance ceramic tiles. It was also found that the presence of waviness contributes to increasing the floors slip resistance even more. Through regression analysis, a good correlation between the pendulum results and the roughness parameter Ra was found.

Ceramic Floor Tiles from the Excavation at Sobornaya Square in Tver (Based on Researching of 2013–2014)

В статье представлены результаты исследований коллекции керамических плиток пола, полученной при раскопках на месте тверского Спасо-Преображенского собора 1285 года. Проведен анализ морфологических и технологических признаков, реконструирована технология изготовления изделий, выделены типы плиток, установлена хронология находок. Полученные результаты позволили установить отдельные этапы использования в интерьере собора керамических плиток и реконструировать их разновременные наборы. Среди обнаруженных находок удалось выделить плитки XIII в., относящиеся к дособорному деревянному храму – церкви Козьмы и Демьяна. The report deals with research results of ceramic floor tiles collection found during the excavation at the site of non-existent nowadays Transfiguration of the Savior Cathedral built in 1285. The collection was analyzed by its morphological and technological characteristics. Tiles manufacturing technology was reconstructed and they were classified by types and according to finding chronology. These results made it possible to outline separate periods during which ceramic tiles were used as part of the Cathedral interior and reconstruct tiles sets of different periods. There were tiles of the XIII century among these findings which are related to earlier wooden Church of Saints Cosmas and Damian.