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One of the last scientific activities of Ermanno Grinzato was the research on radiant heating and cooling systems. In addition to providing a novel view for thermal and thermographic testing of these systems, he had foreseen the importance of using efficient and sustainable materials. Firstly, this work introduces the issue of testing radiant heating and cooling systems and the arising interest in geopolymers. Afterwards, the synergy between these two research fields is highlighted by the realisation and testing of a novel geopolymeric panel. [ABSTRACT FROM AUTHOR]

The durability of Portland cement mortars is often affected by environmental factors, which can cause physicochemical and mechanical degradation processes. In this study, the performance of three products, calcium acetoacetate and calcium tetrahydrofurfuryloxide dissolved in two different solvents developed and tested as stone consolidants, was evaluated in terms of crack filling or sealing and consolidation. Realistic cracks were induced in quasibrittle cement mortar prisms using a custom-designed test rig. The effectiveness and the performance of the considered treatments, investigated on specimens, were evaluated by optical and scanning electron microscopy, colourimetry, water absorption rate, ultrasonic pulse velocity, and surface hardness measurements. Results revealed that, in the examined conditions, the products were more suitable as surface consolidants than as crack fillers. [ABSTRACT FROM AUTHOR]

The paper presents a Round Robin Test (RRT) devoted to the characterization of the shear bond performance of fibre-reinforced strengthening systems bonded with epoxy resin to brick masonry. The research was carried out by six laboratories involved in the RILEM TC 250-CSM (Composites for the Sustainable strengthening of Masonry) as a continuation and an extension of a previous RRT1 performed within the RILEM TC 223-MSC (Masonry Strengthening with Composites). In this second investigation (RRT2), the same FRP (basalt, carbon and glass textiles) and SRP (comprising steel textiles) composites were tested, but shear bond tests were carried out on both brick units and masonry prisms. The role of the bed joints of mortar was investigated in terms of shear bond strength, load-displacement response curve, axial strains profile along the bonded area and effective transfer length, for each of the four considered strengthening systems. Single lap and double lap testing setups were used and the comparison of experimental outcomes provided a validation of both results and test methods. Finally, test outcomes led to the determination of the mean and the characteristic values of the experimental-based calibration coefficient provided by design codes for the evaluation of the composite-to-substrate bond strength. [ABSTRACT FROM AUTHOR]

The performance of various composite materials applied to strengthen hollow masonry panels under out-of-plane actions is compared here. The strengthening solutions belong to three reinforcement Externally Bonded (EB) wet lay-up systems: (i) bidirectional composite meshes applied with inorganic matrices, i.e., Textile Reinforced Mortars (TRM); unidirectional composite textiles applied with (ii) inorganic matrices, i.e., Steel Reinforced Grouts (SRG), or (iii) organic (epoxy) matrices, i.e., Fibre Reinforced Polymers (FRP), Steel Reinforced Polymers (SRP) and Natural FRPs. Carbon FRP, flax and hemp NFRP, and basalt and glass-based TRM were examined. As inorganic matrix, a cement-based mortar was used for TRMs; in the case of SRGs, comparisons with a magnesia-based matrix were also carried out. Twenty-seven specimens were subjected to simplified four-point monotonic bending tests, aimed at reproducing in the laboratory the failure condition of infill masonry walls under out-of-plane actions. The results are compared in terms of failure mode and mechanical improvement, and provide an analytical evaluation of moment-curvature behaviour according to bilinear laws. [ABSTRACT FROM AUTHOR]

The paper presents the experience of a working group within the RILEM Technical Committee 223-MSC 'Masonry Strengthening with Composite materials', aimed at developing a standardized, reliable procedure for characterizing the bonding mechanism of masonry elements strengthened with composite materials under shear actions. Twelve laboratories from European universities and research centers were involved. Two different set-ups were compared, for single-lap and double-lap shear tests (the latter in two versions). Four kinds of fiber fabrics, i.e., glass, carbon, basalt and steel, were applied with epoxy resins (wet lay-up system) to clay brick units, for a total of 280 monotonic tests. The results provided information regarding the response of externally bonded-to-brick composites in terms of observed failure mechanisms, load capacity, effective transfer length, and bond shear stress-slip behavior. The test results of the 12 laboratories constitute a set of statistically representative data which may conveniently be used for setting appropriate design provisions and guidelines. [ABSTRACT FROM AUTHOR]

The construction and demolition sector is one of the biggest consumers of natural resources in the world and consequently, one of the biggest waste producers worldwide. The proper management of construction and demolition waste (CDW) can provide major benefits for the construction and recycling industry. However, the recycling rate of CDW is relatively low, as there is still a lack of confidence in the quality of recycled CDW materials. Therefore, new research projects are looking for innovative solutions within recycling of CDW in order to overcome uncertainties currently associated with the use of construction products made from recycled or re-used CDW. In this paper, a "cradle-to-cradle" life cycle assessment (LCA) study has been conducted to investigate the environmental performance of the prefabricated geopolymeric façade cladding panels made from large fractions of CDW. The LCA results indicate that the majority of the environmental burden arises within the manufacturing stage; however, the environmental burden can be reduced with simple optimisation of the manufacturing process. Furthermore, the environmental impact of the prefabricated geopolymeric façade cladding panels is generally lower than the environmental burden associated with the façade cladding panels made from virgin materials. [ABSTRACT FROM AUTHOR]