Vincenzo Savino

A timely knowledge of concrete and ultra-high-performance concrete (UHPC) strength is possible through the so-called strength-equivalent time (Et) curves. A timely knowledge of concrete strength is useful, for instance, to precisely determine when the shores of a hardening structural element can be safely removed. At the present time, the preparation of the strength-Et curves requires time-consuming and labor-intensive testing prior to the beginning of construction operations. This paper proposes an innovative method to derive the strength-Et and total heat-Et curves for both normal strength and UHPC. Results confirmed that the proposed method is fast, inexpensive, self-calibrating, accurate and can detect any variation of the concrete mix proportions or components quality. In addition, the quality of predictions of strength–maturity curves can be constantly improved as the specimens’ population increases. Finally, results obtained with the proposed method were compared with those o...

Abstract High Performance Fibre-Reinforced-Cement-Composites and Ultra-High Performance Fibre-Reinforced-Concretes, also named HPFRCCs and UHPFRCs respectively, are today widely used as repair and strengthening existing structures, such as bridge decks, pavements, piers etc. Simple test methods to characterize its mechanical behavior are requested, in order to ensure that the product meets the designer’s requirements, especially in term of tensile behavior. Various test methods are available, even though a proper correlation between direct and indirect tensile (e.g. flexural) tests is needed. In this paper a model based on the “Composite Material Theory” (CMT) was developed to predict the flexural behavior of three commercialized SFRCs once the direct tensile strength is measured. A good agreement was found between experimental results and the values predicted by the model.