The use of tire rubber in the production of high-performance concrete

The advances in concrete technology lead to the search for alternative materials that provide improvements in concrete properties while at the same time collaborating with sustainable practices in construction. In this study, the influence of the incorporation of waste tire rubber on the mechanical properties of high-performance concrete was discussed. The waste rubber from the tire retreading process was used in partial substitution of the fine aggregate (sand) in the percentages of 7.5%, 15% and 30% with respect to the mass of the sand. For the characterization of the concrete, the following tests were carried out: water absorption, void index, specific density, compressive strength, flexural tensile strength, modulus of elasticity and microscopy analysis. The incorporation of rubber as aggregate in high-performance concrete proved to be promising for the production of a structural concrete with special characteristics, besides collaborating with the proper disposal of waste tires651110114sem informaçã

Study of the reuse of construction residues in concrete employed by blocks manufacture

The use of construction and demolition waste (CDR) comes as an alternative for recycling, for costs reduction and for raw material. The CONAMA Resolution 307 (National Council for the Environment) establishes that all cities should find an environmentally correct destination to CDR. In this research the mechanical properties of the concrete containing CDR were analyzed aiming its use in the production of concrete blocks. Here, increasing percentages of aggregates of CDR with the same granulometry an substitute the natural aggregate, and then concrete blocks were molded. Tests were then performed in order to determine the compression strength according to NBR 12118:2007, at ages of 14 days and 28 days. It was noticed that the values resulting from the compression strength test were also influenced by the increasing substitution of CDR percentages to the mixture. This research discusses the great potential of using this material in substitution to the natural aggregates used in the production of concrete based materials such as blocks

Analysis of composite steel and concrete columns at high temperatures

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOThe growing demand for knowledge about the effect of fire on structures has stimulated research worldwide. This article presents experimental results of short, composite columns made of steel and concrete when submitted to high temperatures in furnaces, with and without axial compression loading, as well as a numerical analysis of the temperature distribution in these columns. The columns were modeled as concrete-filled tubes with three thicknesses and two diameters considered. In addition, standard fire temperature-time curves were obtained experimentally for use in the numerical calculations. Copyright (c) 2014 John Wiley & Sons, Ltd.The growing demand for knowledge about the effect of fire on structures has stimulated research worldwide. This article presents experimental results of short, composite columns made of steel and concrete when submitted to high temperatures in furnaces, w402305317FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOsem informaçã

Rubberized mortar: the influence of aggregate granulometry in mechanical resistances and acoustic behavior

The incorporation of rubber waste from tires into cementitious elements has become an increasingly recurrent practice, since this activity fosters the idea of sustainable construction. The use of rubber as an aggregate in the mortar promotes the correct destination of this residue, becoming inert, promoting the hygiene of the environment. Many researchers have studied the physical and mechanical behavior of rubberized mortar. However, particle geometry analyzes are scarce. This research aims to study the incorporation of rubber tire residues in mortars in two grades of granulometry, i.e., spheroids (S) and fibers (F), replacing the conventional aggregate in 7.5%, 15% and 30%. Density, compressive strength, flexural strength, microstructure and sound attenuation tests were performed. Rubber mortars showed a reduction in density of up to 34.6% compared to conventional mortar, consequently resulting in a reduction of approximately 4 times in compressive strength. However, there is a better acoustic behavior, especially when the rubber is used in fiber format, which presents 29.70% and 42.54% of attenuation enhancement for 15% of fiber waste tire rubber, considering P- and S-waves, respectively20024825

The use of tire rubber in the production of high-performance concrete

Abstract The advances in concrete technology lead to the search for alternative materials that provide improvements in concrete properties while at the same time collaborating with sustainable practices in construction. In this study, the influence of the incorporation of waste tire rubber on the mechanical properties of high-performance concrete was discussed. The waste rubber from the tire retreading process was used in partial substitution of the fine aggregate (sand) in the percentages of 7.5%, 15% and 30% with respect to the mass of the sand. For the characterization of the concrete, the following tests were carried out: water absorption, void index, specific density, compressive strength, flexural tensile strength, modulus of elasticity and microscopy analysis. The incorporation of rubber as aggregate in high-performance concrete proved to be promising for the production of a structural concrete with special characteristics, besides collaborating with the proper disposal of waste tires