Flexural Strength Evaluation of Nonconstant Thickness Ceramic Floorings by Means of the Finite-Element Method

摘要

The ceramic tile industry has become an extremely competitive sector. The entry of new Asian and South American manufacturers into the market is shifting the leadership in production and exports from the traditional clusters of Europe to China, Turkey, and Brazil. In this uncertain environment, enterprises should raise the quality and cut costs by means of new products and processes. Ceramic tiles lightened by carving of a deep back relief could give rise to a generation of new, efficient products. These tiles could be manufactured with fewer raw materials than the traditional ones, which may lead to saving of weight and energy. Additionally, a lighter final product improves working conditions on the shopfloor and at the building site. Nevertheless, lightened tiles are structurally different from traditional ones, and so is their mechanical behavior. Because tiles are constructive elements, it is necessary to know their response under typical loads and assure fulfillment of the valid standards.rnThis paper aims at evaluating the flexural strength (R) of lightened ceramic floorings using solid three-dimensional modelling and the finite-element method, establishing a new formula for the application of the international standard ISO 10545 "Ceramic Tiles." In order to achieve this objective, one reference model and 48 different relief versions were designed, which underwent a simplified computational simulation of the bending test. In accordance with the Rankine criterion, the maximal stresses of each version were calculated, as much as their distribution. Next, we correlated the results defining a new parameter called "normalized thickness," defined as the thickness that a carved tile should have to behave as a traditional flooring under flexion. This parameter allowed the adjustment of the international standard ISO 10545 to this kind of a product, facilitating their certification and therefore their real introduction in the market. Finally, thanks to the collaboration of the company Keros Ceramica S. A., it was verified that the methodology used was appropriate.