Mechanical Behavior of Concrete with High Absorption Limestone Aggregate and Multi-walled Carbon Nanotubes

Carbon nanotubes have demonstrated their versatility in the manufacture of various devices such as molecular probes, pipes, cables, fibers and springs. Recently, they have been used in cement composites to improve their physical and mechanical properties, but there are still many questions regarding the physical-mechanical behavior that can be achieved in structural concrete. In view of this, the present work aimed at the designing of concrete mixtures with multi-walled carbon nanotubes additions, in order to minimize the unfavorable conditions caused by high absorption limestone aggregates and to improve the mechanical properties compared to regular concretes. Results showed improvements in the microstructural development, compressive strength (7 -11%), splitting tensile strength (14-16%) and modulus of elasticity of the concrete (8-12%). However, some issues related to the functionalization and dispersion of the nanotubes in the mixtures remain to be solved to advance their utilization.