Forjados de placa alveolar con continuidad activa mediante el uso de aleaciones con memoria de forma en base hierro = Hollow-core slab slabs with active continuity using iron-based shape memory alloys

Abstract

[eng] In recent years, the use of iron-based shape memory alloys has grown exponentially in the construction sector, especially in rehabilitation in Central European countries. This innovative material can be used as prestressing in reinforced concrete due to its shape memory effect and can generate compressive stresses in concrete elements without the use of hydraulic jacks, sheaths, anchorage devices or other accessories. These alloys are currently available on the European market in the form of rebar or strip. This article evaluates the benefits of using iron-based shape memory alloy rebars as active continuity in precast hollow core slabs, more specifically, their construction process and effectiveness, based on the most relevant results of the experimental campaign. Finally, the improvements in the Serviceability Limit State are presented by implementing the active continuity compared to a continuity without prestressing, i.e., with the shape memory alloy on an inactivated iron basis. To conclude, it is demonstrated that using this technology delays the cracking process and improves the stiffness of the elements.