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The most common test methods used to evaluate alkali-silica reaction (ASR) are the concrete prism test (CPT) and the accelerated mortar bar test (AMBT). However, these tests were not found to be entirely reliable in predicting the performance of concrete under field conditions, especially when supplementary cementitious materials (SCMs) are used. Recently, two new test methods, the miniature concrete prism test (MCPT) and the concrete cylinder test (CCT), have been proposed but still need to be benchmarked with results from outdoor exposed blocks. In this paper, the results from the MCPT, CCT, CPT and exposed blocks are compared and their ability to properly evaluate the expected behavior of these mixtures in service with regard to ASR is discussed. Here, the results of mixtures made with four reactive aggregates: Spratt, Placitas (coarse aggregates), Wright, and Jobe (fine aggregates) and SCMs (fly ashes Classes F or C, slag cement, or silica fume) at different levels of cement replacement or lithium nitrate are presented. For these mixtures, only the MCPT was capable of properly classifying the efficiency of the ASR preventive measures, as compared with the long-term results obtained from the exposed blocks.

An approach to the production of ceramic drug delivery devices is proposed. Two examples of possible ceramics are dealt with: hydroxyapatite weakly modifiable by living tissue and the bioinert alumina. The possibility to control the formed porosity was taken into consideration for both materials. The ratio between the acquired porosity and the quantity and quality of the agents inducing porosity is also described and discussed. A test on the role of porosity was performed on the obtained porous ceramic bodies and a study was made on the release of a substance with pharmacological activity from previously impregnated porous ceramic bodies. This paper is preliminary to a planned work targeted to the preparation of ceramic drug delivery systems.

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The seismic events that struck the Italian region Emilia-Romagna in 2012 provoked not only numerous injuries and casualties but also vast damage to thousands of buildings, infrastructures, and production sites. In particular, unlike other Italian sequences, that of 2012 was notable for the high value of losses in the industrial sector. Soon after the earthquakes, plans were set up in order to provide financial help to both citizens and enterprises, and to this aim the regional authority gathered and classified damage and loss reports. Information was collected in a database called SFINGE. This study is an empirical data analysis of a consistent subset of SFINGE, whose elements are long-span-beam buildings used as production sites. Results are in terms of direct economic losses and cost of reconstruction. This work is a precious source of seismic economic consequence assessment tools for the considered building typology, within the framework of Performance-Based Earthquake Engineering.

The use of superabsorbent polymers (SAPs) in cementitious materials has attracted much attention recently due to the potential benefits associated with internal curing. In this study, a commercially produced SAP is characterized using pore solution absorption and desorption measurements. The SAP helps maintain higher internal relative humidity in the pastes, resulting in a reduction in autogenous shrinkage. This paper explores the effects of partial SAP replacements and compares the results to those obtained using a previously developed relationship based on pore size distribution and relative humidity measurements, which aims to predict the reduction in shrinkage coming from additional internal curing water. Using this approach reduces the amount of SAP used for internal curing, as compared to the more conventional design methodology, which is based on providing a volume of internal curing water that is equivalent to the total chemical shrinkage. Experimental data showed that only a fraction of the provided internal curing water ends up filling the pores and reducing the autogenous shrinkage. Other factors, such as increased degree of hydration and partial desorption of the internal curing agent, account for the sharing of the available internal curing water. The aforementioned approach was modified to consider these factors. It can be concluded that using lower amounts of SAP results in substantial reduction of autogenous shrinkage at early ages, and the developed relationship predicts this shrinkage reduction.

Pore solution expression is an established method to obtain samples of the liquid phase from cementitious systems. This experimental method applies pressure to a cementitious sample, forcing its liquid phase out of the pores. By collecting and studying the liquid phase in cementitious systems, it is possible to obtain information on its ionic concentrations. The ionic concentrations can be used for modeling calibrations and to estimate the resistivity of the pore solution. When the bulk resistivity of concrete is normalized by the pore solution resistivity, it is possible to determine the formation factor. The formation factor is related to the transport properties of the concrete and, as such, it can be used to estimate the rates of transport of ionic species within a concrete structure. The formation factor is currently being included in AASHTO PP84, Standard Practice for Developing Performance Engineered Concrete Pavement Mixtures, as an indicator of transport properties for quality control operations. Pore solution expression is included as one of the available procedures of AASHTO PP84-19 to determine the pore solution electrical resistivity. Previous studies on paste and mortar samples have demonstrated that increased loading pressure during the pore solution expression might impact the final ionic concentrations of the expressed solution. This study aims to verify if the pore solutions of concrete specimens are also influenced by the selected loading pressure and whether the potential consequent change in the measured ionic concentrations of the solution also has an impact on its resistivity. No appreciable trend in increased solubility was observed for the range of applied normal pressures between 600 and 985 MPa. Cyclic loading regimes increased the variability of alkali solubility. Sample preparation, in some cases, influenced the water content of the sample and induced unwanted alteration on the ionic concentrations of the mixtures under study.

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