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Within the PARTNER project (2002–2006) concrete cubes were exposed for 13 years at different exposure sites in Europe. Subsequently, cores were extracted from these cubes for further investigation within the framework of RILEM TC 258-AAA. The aim of the microstructural study is to relate the microstructural features to cube expansion and to investigate a possible relation between aggregate type and chemical composition of ASR product. Both the Damage Rating Index (DRI) determined on polished sections and the Qualitative Damage Assessment (QDA) performed on thin sections show a relation to cube expansion. However, damage characteristics depend on the texture and composition of the aggregates, affecting the results of both used methods. The composition of ASR products formed in aggregate particles varies in a very small range showing no systematic influence of aggregate type or exposure site.

Coal bottom ash waste obtained from thermoelectric power plants could be recycled like any other new cement constituent when sufficiently ground. Such a proposal would result in a reduction of both energy consumption and CO2 emissions from cement production, while minimising the environmental impact of disposing of the coal bottom ash in landfill sites. The new cement constituent must guarantee at least the same durability than that of cements in current use. In order to assess the viability of using the coal bottom ash as the new main constituent of Portland cements, a comparative study with coal fly ash supplied by the same power plant was conducted. Coal fly as and ground coal bottom ash were used to replace 10% and 25% of the weight of the Portland cement. Natural chloride diffusion and chloride migration, as well as electrical resistivity, were determined in the concrete. Concretes made with 25% of coal bottom ash result in lower migration and diffusion coefficients (Dnssm = 0.98·10−12 and De = 0.42·10−12) than concretes with 10% (Dnssm = 4.12·10−12 and De = 1.33·10−12). These coefficients are lower than those for coal fly ash for the same ash content of 25% (Dnssm = 3.82·10−12 and De = 1.26·10−12) or 10% (Dnssm = 7.06·10−12 and De = 3.80·10−12). In addition, concretes made of cements with 25% of ground coal bottom ash showed significant higher resistivity values than coal fly ash concretes with ages over 28 days. These results can be explained by considering the higher fineness of the ground coal bottom ash.

This paper assess the mechanical an environmental behaviour of cement mortars manufactured with addition of fly ash (FA) and bottom ash (BA), as partial cement replacement (10%, 25% and 35%). The environmental behaviour was studied by leaching tests, which were performed under several temperature (23 °C and 60 °C) and pH (5 and 10) conditions, and ages (1, 2, 4 and 7 days). Then, the accumulated amount of the different constituents leached was analysed. In order to obtain an environmental burden (EB) value of each cement mixture, a new methodology was developed. The EB value obtained is related to the amount leached and the hazardous level of each constituent. Finally, the integral study of compressive strength and EB values of cement mixtures allowed their classification. The results showed that mortars manufactured with ordinary Portland cement (OPC) and with coal BA had similar or even better environmental and mechanical behaviour than mortars with FA. Therefore, the partial replacement of cement by BA might be as suitable or even better as the replacement by FA.

In the composition region of PZT rich in zirconium, (0.05 < x < 0.35) there are two phase transitions. The first takes place between the high and low temperature Rhombohedric phases FRL–FRH both of which are ferroelectric, and the second between the high-temperature ferroelectric Rhombohedric phase and the cubic phase which is paraelectric (FRH–PE). The phase FRL–FRH transition of the PZT system has been studies using different methods. In all of the cases, the fundamental difficulty in establishing the transition characteristics has been the small alteration in the electrical parameters of this transition. In this work, we have verified, when the samples being studied are polarized, the changes are intensified significantly, undoubtedly allowing both the characterization of the transition temperature and its nature. In order to carry out our study, we have selected several PZT compositions doped with niobium, by moving the Zr/(Ti + Nb) > 90/10 region, in which we have determined the characteristics of the transition phase and the influence of niobium on it.

Electroceramics with ferropiezoelectric and ferri-ferromagnetic properties have been studied. These ceramics consist of two phases, a ferroelectric one (commercial BaTiO3) and a ferromagnetic one (MFe2O4, with M = Ni, Zn, Co, obtained through co-precipitation methods), which are later mixed using mechanical milling. A characterization of the previous phases is made by means of electronic microscopy and X-ray diffraction. The results of the magnetic, electric, ferroelectric and piezoelectrical response of the different compound compositions are obtained. The coexistence of phases is made clear, with a greater magnetic response in the samples of ferrite with Co and a greater piezoelectric in the samples of ferrite with Ni. These results are analysed, and the potential of the use of different mixtures is discussed.

In this paper, solid phase sintering of a natural anhydrite-glass composite from powders of these materials is described. The microstructure of the sintered material has been analysed by means of scanning electron microscopy and X-ray emission. Some properties of this new material have been determined. Specific applications for this new sintered material are suggested.