Thermomechanically micromechanical modeling of prestressed concrete reinforced with shape memory alloy fibers

Concrete is a very popular material in civil engineering, although it exhibits some limitations. The most crucial limitation is its low tensile strength, compared to its compressive strength, which results from the propagation of micro-cracks. This may be prevented by using prestrained shape memory alloy wires that are embedded in the concrete matrix. Upon activation, these wires regain their original shape, and consequently initial compressive stresses are transmitted to the concrete matrix. In this study, a thermomechanically micromechanical model of prestressed concrete reinforced by shape memory alloy fibers is presented and examined for different reinforcement aspects. It was found that there is a strong relation between the activation temperature deviation and the behavior of the prestressed concrete. The relation between the fiber's volume fraction and the composite response and the effect of the shape of the reinforcing fibers and residual strain orientations is examined in detail.