Numerical Modelling of Innovative Deconstructable Shallow Beams Made of Recycled Aggregate Concrete and Shape Memory Steel Reinforcement

Nowadays, the construction industry increasingly demands sustainable structural solutions, where life extension through increased durability can be combined with the ability to deconstruct such systems and reuse them in other contexts. Following a recent research project that investigated the potential of structural modules made of recycled aggregate concrete (RAC), joined and prestressed with iron-based shape memory alloy bars, the paper aims to numerically simulate the flexural response of innovative shallow beams for slab applications. In particular, emphasis is placed on: i) extrapolation of key mechanical parameters from standard material characterization tests; ii) simulation of the initial stage of thermally-activated pre-stressing; and iii) nonlinear analysis of the behavior of full-scale prototypes subjected to 4-point bending tests. The purpose is to clarify the behaviors observed in the testing campaign, providing useful guidance for the design of similar structures. The results of the analyses will be compared with experimental measurements provided by multiple transducers in both the pre-stressing and testing phases, and through the comparison of equivalent plastic strains with the failure modes and the cracking patterns detected at the end of the experiments.