Influence of the Physical and Mechanical Properties of Concrete by Adding Rubber Powder and Silica Fume

The construction sector has been consuming raw materials that are becoming extinct over time; in order to contribute to the sustainability of these resources, the use of wastes that are produced on a large scale and often expelled into the environment without being well exploited, there we have the tire rubber and silica fume. This study seeks to evaluate the physical-mechanical properties of concrete, using rubber powder (RP) and silica fume (SF), as a partial substitute for fine aggregate and cement. Concrete samples were made using 5%, 7%, 11% and 14% of rubber powder plus 3%, 7%, 11% and 15% of silica fume. The physical properties were evaluated by slump, temperature and unit weight tests, while compression, tensile and flexural tests were developed at 7, 14 and 28 days of curing, to analyze the mechanical properties. The results showed that the physical properties maintain acceptable variations, since the deficiencies of the rubber powder are reduced by the silica fume; the properties of compression, flexion and traction revealed that even with 8% of rubber powder plus 7% or 11% of silica fume, the desired resistances can be reached, without presenting increases. It is concluded that partial substitution with rubber powder and silica fume does not contribute significantly to the properties of concrete, however, it can be a great alternative when high strength concrete is not required.