Bending characteristics of resin concretes

Abstract

In this research work the influence of composition and curing conditions in bending strength of polyester and epoxy concrete is analyzed. Various mixtures of resin and aggregates were considered in view of an optimal combination. The Taguchi methodology was applied in order to reduce the number of tests, and in order to evaluate the influence of various parameters in concrete properties. This methodology is very useful for the planning of experiments. Test results, analyzed by this methodology, shown that the most significant factors affecting bending strength properties of resin concretes are the type of resin, resin content and charge content. An optimal formulation leading to a maximum bending strength was achieved in terms of material parameters. cal and corrosion properties of such concretes allow thinner cross-sections and lower cover depths in reinforced concrete , reducing transport costs and handling risks. As Portland cement concrete, resin concretes relatively have low tensile strength, when compared to compressive strength (around 100 MPa). Therefore, brittle cracks due to tensile stresses can occur, making it necessary in many cases to use steel or FRP rebars, increasing ultimate load, ductil-ity and toughness 3-6. The main objective of this work is to analyze the influence of mixture and curing cycles in the bending behaviour of polyester and epoxy concretes. The planning of various mixtures was achieved with a Taguchi methodology. This technique allows an analysis of the effect of several manufacturing factors 7-11. This technique also allows the identifying of interactions between factors, reduction of mixture combinations through a library of pre-set orthogonal matrices, without loss of relevant information 7-11. To perform all possible tests with all possible mixture combinations would not be practical , neither in time nor cost.