Masonry structures are very sensitive to out-of-plane mechanisms under horizontal actions. A common traditional technique to avoid or mitigate the activation of these mechanisms is represented by injected anchors made of steel bars aimed to improve the connections between orthogonal masonry walls or between floors and masonry walls. The bars are usually embedded in the masonry by means of cement-based grout in holes realized inside the elements to be connected. Recently, an increased interest has developed in the scientific community about the use of Fibre Reinforced Plastic (FRP) bars as alternative to the steel ones for injected anchors, mainly because of their high tensile strength and inertia to corrosion, which can give them high durability, in addition to the use of high-performance grouts. The paper reports the results of experimental pull-out tests realized by the Authors on several types of FRP bars used as injected anchors in small masonry specimens made of yellow tuff blocks. A hydraulic lime and pozzolana-based grout is used to fix the bars in holes realized in the masonry specimens along an embedded length of 250 mm. The set-up is realized in order to apply pure tension to the bars and shear stresses along the bar-grout and the grout-masonry interfaces. The results are analysed in terms of maximum pull-out forces, failure modes and force-displacement relations in order to evidence the global performance of each tested system, especially in relation with the diameter and the surface treatment of the bars. Some comparisons with literature formulation for predicting the pull-out force are developed too.

In this paper, the mixture designs of the concrete in durable reinforced and prestressed structures of a viaduct for a railway train connecting Venice directly with Cortina are illustrated. Three mixture designs, based on the European Norms for the 100-year durable concrete reinforced or prestressed structures of the above construction, are developed as a function of the environmental region crossed by the viaduct of this railway train. The first region of the travel connects the Santa Lucia railway station in Venice with the mainland where the reinforced and prestressed concrete structures are exposed to tidal, splash, and spray zones of the close seawater. The second region crossed by the viaduct of the railway train is the oriental Po Valley exposed to air and rain and then to the penetration of CO₂ with the risk of corrosion of the metallic reinforcements. The last region crossed by the viaduct of the railway train is a large area of up to 1,500 m (4,920 ft)-high mountains and is exposed in winter seasons to freeze-thaw cycles. A pozzolanic cement type CEM II-B/V 42.5 N, with about 20% Portland cement replaced by siliceous fly ash, is recommended to ensure that the alkali-reactive aggregates, if any, are neutralized by the presence of fly ash. For structural reasons, a cube characteristic strength (fcu/ck) of 50 MPa (7,250 psi) is prescribed for all the viaducts crossing the three regions.

High purity lithium hydroxide and lithium carbonate for use in lithium-ion batteries are produced by the processing of spodumene ore from the Whabouchi mine (Northern Quebec, Canada). The main byproduct of this treatment is an aluminum silicate waste stream, which is produced in very large quantities and should be recycled to avoid its storage in landfills, which is not environmentally friendly. Previous research work by the authors on the characterization of this aluminum silicate waste stream showed its potential as a pozzolanic material and hence that it could be used by the cement and concrete industry, which would contribute to the sustainability of these industries. The purpose of this study was to assess the pozzolanic activity of this new material and its effects on the properties of concrete in its fresh and hardened states in order to evaluate the effects of replacing part of the cement with this aluminum silicate waste stream in various classes of concrete. Series of air-entrained and non-air entrained concrete mixtures were produced and tested in this study. Results from fresh state testing, mechanical and durability properties of the concrete made with this material were similar to those obtained with conventional supplementary cementitious materials and equal or superior to those obtained with reference concrete mixtures made with plain and ordinary portland cement.

This paper analyzes waste fines generated during the mining, crushing, and washing of aggregates in quartzite quarries (Mar del Plata, Argentina). The waste fine consists mainly of a mixture of quartzite and clay. The characterization of the materials included chemical analysis, XRD, TGA, particle size distribution, morphology, and composition of particles by SEM-EDS. Both the dry raw materials and the calcined material (temperatures of 500º C, 700º C, and 950º C) were analyzed. The pozzolanic activity of the calcined powders at different temperatures was evaluated by the modified Chapelle method. The original composition of the material, consisting of angular quartz, kaolinite "face to face" and laminar illites, was modified as calcined clays vary in their morphology and mode of aggregation due to the effect of temperature. The result of the TGA showed some limited loss on ignition (3%) between 400º C and 800º C, reflecting the dehydroxylation of clays. The pozzolanic activity effectively increased with increasing calcination temperature. Therefore, the material is considered to have pozzolanic activity when thermally activated.

Sustainable development and circular economy policies currently prioritize the recovery of industrial waste and rubble as secondary raw materials. Concrete and demolition waste's (CDW) fine fractions of concrete nature are bringing special attention due to their accumulation, subject to weather conditions, and without any industrial application at present. These wastes have little pozzolanic activity, which is why it is necessary to combine them with other active additions for the ternary cements manufacture. At present, a laminar glass waste from the deconstruction has been selected to obtain the binary mixture. A binary mixture of pozzolan recycled concrete/glass with a 1:2 ratio has been prepared to evaluate the synergy of both wastes in the pozzolanic reaction, and its possible commercialization for future ternary cements that are more sustainable. The characterization of materials and reaction kinetics mainly in the ternary pastes have been characterized by XRF, ICP/MS, NMR, FTIR, XRD-Rietveld, and SEM/EDX, detecting calcite, quartz, mica, feldspar, and clay minerals and as hydrated phases ettringite, aluminates and C-S-H gels. According to these results, it can be highlighted that from the scientific point of view, this mixture of pozzolans from CDWs is viable for use as ecoefficient pozzolans for the more sustainable ternary cements.