Investigation on the properties of concrete tactile paving blocks made with recycled tire rubber

• Concrete with replacement of 10–50% of natural sand for tire rubber.
• Excellent compressive strength and flexural strength results.
• With the addition of rubber there was an improvement in abrasion resistance.
• The tire rubber has high performance to use as concrete’s aggregate.

Due to the increasing demand for buildings that meet accessibility standards and give access to all users, without restriction to people with a disability or reduced mobility, it arises the search for efficient and quality products. Aiming to develop a concrete paving block that contributes to sustainability in building and to accessibility in the built environment, in this paper recycled tire rubber (crumb rubber) was used as aggregate in concrete to produce tactile paving block. The replacement was made in relation of the mass of sand at the level of 10%, 20%, 30%, 40% and 50%. The concrete characterization was performed by testing the consistency, compressive strength, flexural strength, water absorption, porosity, density, abrasion resistance, impact resistance and microstructure analysis. Although the major limitation of using crumb rubber as aggregate in the concrete is to reduce the compressive strength, the results reached were higher than 40 MPa for the paving blocks with the inclusion of 50% of crumb rubber. The results of flexural strength obtained to all concrete mixes studied were higher than 6.5 MPa. It was found that concrete containing rubber showed a better abrasion resistance.