Verification of the use of the pseudoelastic Nickel-Titanium alloy as reinforcement in a concrete beam
Shape Memory Alloy; Smart materials, Flexural test, Special structures.
The use of reinforced concrete in the construction industry is widespread around the world and this makes some aspects need to be characterized in several technical aspects; it is a material that does not have good behavior in case of dynamic loads, due to its great rigidity and little, if any, deformation. Therefore, the proposal to use the Nickel-Titanium (NiTi) alloy as reinforcement in concrete tends to favor the recovery of deformations of a structural element and avoid abrupt collapse. This experimental research is limited to the verification of the mechanical behavior of a beam in bending and is mainly based on the international standard ASTM C78. The specimens were manufactured with conventional steel reinforcement and Nickel-Titanium reinforcement; and, tested, carefully following the requirements suggested by the technical standard in force. The results showed that, for the conventional steel, bending strength of 7.37 ± 0.67 MPa and displacement of 10.47 ± 0.47 mm were obtained, making it possible to verify that the conventional steel reinforcement supported greater stress compared to Nickel-Titanium, however, lower displacement; for the Nickel-Titanium reinforcement, the beam presented a mechanical bending strength of 5.42 ± 0.44 MPa and a displacement of 67.30 ± 1.46 mm, demonstrating that the system resisted 26.48% less in bending, however, the displacement was about 642.79% greater in relation to steel reinforcement and also showed partial recovery of the initial position of the beam even after complete failure of concrete.