HPFRCC BEAMS IN INNOVATIVE ELEVATED SLABS: EXPERIMENTAL CHARACTERIZATION AND MODELING

In the field of precast structures, the need to ensure robustness, ductility, fire resistance and rapid assembly, moves designers and researchers towards the development of innovative structural solutions, making use of high-performance materials [1, 2] which allow to optimize the elements sections, while reducing the total masses and the execution costs. This is the case of a semi-precast slab floor composed by HPFRCC beams coupled with TRC disposable formworks and a SFRC finishing casting, which is actually the topic of a research project held at Politecnico di Milano [3]. In this framework, the secondary HPFRCC beams were designed according to the fib Model Code 2010, paying attention on both the transient and the service conditions. Following the experimental characterization of the plain material (by means of bending tests on notched beam specimens and compressive tests on cylindrical specimens), two full-scale beams (3.4 m long) were cast and experimentally validated by means of four-point bending and shear tests. The results were finally compared with simplified analytical models based on plane-section hypotheses, proving the predictive capability of the available design tools.