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Granite is one of the most commonly employed materials in the production of aggregates for concrete, and represents 40% of the total volume of aggregates produced in Portugal. This type of rock is traditionally considered as slowly/late reactive or even non-reactive to alkalis. However, a number of cases of damaged concrete structures in Portugal, due to alkali–silica reaction, have been related to granitic aggregates. A research program has been developed in order to define the best test method for evaluating the potential alkali-reactivity of granitic rocks. The present study involved thirteen granites collected from different quarries. The tests carried out included: petrographic examination of the aggregate, as well as mortar and concrete expansion tests. It was concluded that the content of microcrystalline quartz correlates better with the results of concrete prism expansion tests than with the mortar-bar expansion test. 63–77pp The authors would like to acknowledge LNEC, ICT (University of Porto) and Fundação para a Ciência e Tecnologia (FCT) for the financial support of the Project IMPROVE (Ref: PTDC/ECM/115486/2009) and COMPETE 2020 through the ICT project (Ref: POCI-01-0145-FEDER-007690). The author V. Ramos is grateful to FCT towards the financial support of her PhD studies (Ref: SFRH/BD/47893/2008). 86 DM/NMM Cement and Concrete Research

Work is going on in several countries to try to develop a reliable performance testing concept for ASR. This topic was also focused on in the Norwegian R&D project "COIN" (2007-2014). The work was closely linked to the work within RILEM TC 219-ACS (2006-2014). This paper gives a summary of the main findings in the COIN program. The main aim of part I (PhD study) was to document the effect of various curing – and storage conditions on the concrete internal moisture state, the extent of alkali leaching and ASR related expansion. The study documented that the main parameter controlling the ASR expansion measured in the laboratory is extent of alkali leaching. Based on the findings in part I, a comprehensive follow-up study (part II) has been performed. 20 different concrete mixtures, including six aggregate types and four cement types, have been performance tested according to the most promising test procedures in part I. Moreover, two field exposure sites have been established in order to document the laboratory/field correlation, one in Norway (at SINTEF) and one in Portugal (at LNEC). 10p The authors gratefully acknowledge the financial support for the Norwegian COIN project (2007-2014) (www.coinweb.com). DM/NMM

La osteogénesis imperfecta (OI), es una patología poco frecuente y muy heterogénea desde el punto de vista clínico y genético. Su característica principal es la fragilidad ósea, habiéndose descrito varios tipos. Generalmente es causada por mutaciones en los genes que codifican para las cadenas α1 y α2 del pro-colágeno tipo 1 (COL1A1 y COL1A2) con herencia autosómica dominante. Comunicamos los casos de dos pacientes (padre e hija) con OI cuyo estudio genético muestra una mutación en COL1A1 no conocida previamente: la deleción de una Guanina, G(c.3524delG). Se repasan aspectos clínicos, de herencia y opciones reproductivas de los pacientes afectados. Osteogenesis imperfecta (OI), is a rare condition which is heterogeneous in clinical and genetic terms. Several types have been described and its main feature is bone fragility. It is generally caused by gene mutations in those genes which codify for the α1 and α2 of the type 1 collagen (COL1A1 and COL1A2) with dominant autosomal heredity. We report the case of two relatives (father and daughter) with OI whose genetic study shows a mutation in COL1A1 previously undetected: the deletion of a Guanine, G(c.3524delG). Clinical aspects, heredity and reproductive options of the patients affected are considered.

Due to their spatial complexity and dynamic nature, floodplains provide a wide range of ecosystem functions. However, because of flow regulation, many riverine floodplains have lost their characteristic heterogeneity. Restoration of floodplain habitats and the rehabilitation of key ecosystem functions has therefore become a major goal of environmental policy. Many important ecosystem functions are linked to organic carbon (C) dynamics in riparian soils. The fundamental understanding of the factors that drive the processes involved in C cycling in heterogeneous and dynamic systems such as floodplains is however only fragmentary. We quantified soil organic C pools (microbial C and water extractable organic C) and fluxes (soil respiration and net methane production) in functional process zones of adjacent channelized and widened sections of the Thur River, NE Switzerland, on a seasonal basis. The objective was to assess how spatial heterogeneity and temporal variability of these pools and fluxes relate to physicochemical soil properties on one hand, and to soil environmental conditions and flood disturbance on the other hand. Overall, factors related to seasonality and flooding (temperature, water content, organic matter input) affected soil C dynamics more than soil properties did. Coarse-textured soils on gravel bars in the restored section were characterized by low base-levels of organic C pools due to low TOC contents. However, frequent disturbance by flood pulses led to high heterogeneity with temporarily and locally increased pools and soil respiration. By contrast, in stable riparian forests, the finer texture of the soils and corresponding higher TOC contents and water retention capacity led to high base-levels of C pools. Spatial heterogeneity was low, but major floods and seasonal differences in temperature had additional impacts on both pools and fluxes. Soil properties and base levels of C pools in the dam foreland of the channelized section were similar to the gravel bars of the restored section. By contrast, spatial heterogeneity, seasonal effects and flood disturbance were similar to the forests, except for indications of high CH4 production that are explained by long travel times of infiltrating water favouring reducing conditions. Overall, the restored section exhibited both a larger range and a higher heterogeneity of organic C pools and fluxes as well as a higher plant biodiversity than the channelized section. This suggests that restoration has indeed led to an increase in functional diversity.

International audience; A ferritic oxide dispersion strengthened steel is under study for fuel cladding applications in future nuclear systems. Tensile tests and creep tests are carried out at various temperatures to determine its mechanical properties along the extrusion direction. For these two types of loading, the material exhibits a high mechanical resistance. Its ductility appears to be strongly influenced by the strain rate and the temperature. Deformation mechanisms linked to diffusion phenomena are suspected and intergranular damage is observed on fractured specimens.

Interpolation of a spatially correlated random process is used in many scientific domains. The best unbiased linear predictor (BLUP), often called kriging predictor in geostatistical science, is sensitive to outliers. The literature contains a few attempts to robustify the kriging predictor, however none of them is completely satisfactory. In this article, we present a new robust linear predictor for a substitutive error model. First, we derive a BLUP, which is computationally very expensive even for moderate sample sizes. A forward search type algorithm is used to derive the predictor resulting in a linear likelihood-weighted mean procedure that is robust with respect to substitutive errors. Monte Carlo simulations support the theoretical results. The new predictor is applied to the two SIC2004 data sets and is evaluated with respect to automatic interpolation and monitoring.

The usefulness of accelerated test methods for AAR, such as the mortar bar test ASTM C-1260, the various autoclave tests and the proposed Chinese concrete microbar test (RILEM AAR-5) depends on their being reasonable correlation between expansion in the concrete prism test and in the accelerated tests. Results of concrete prism tests run at 38°C are widely regarded as providing the best correlation with the performance of field concrete. The protocol for the concrete microbar test is similar to that of ASTM C 1260 except that the aggregate grading is 12.5 mm to 4.75 mm, the bar size is 40 x 40 x 160 mm and the mixture proportions are one part portland cement to one part aggregate. The concrete microbar test that was originally developed for the evaluation of alkali-carbonate reactive aggregates has been found to also be effective with alkali-silica reactive aggregates. A number of assorted aggregates from several countries were selected for evaluation in the concrete microbar test and in the concrete prism test (CSA A23.2-14A). The test results for siliceous limestones showed that there is good correlation between expansion in this test and in the concrete prism test. The proposed expansion limit is 0.09% at 30 days. No correlation was found between expansions in the two test methods for assorted siliceous aggregates including greywackes, sandstones, volcanic rocks, gravels and cataclastic rocks. However, aggregates in bars showing less than 0.04% expansion at 30 days were classed as innocuous in the concrete prism test. In the microbars, made with all the aggregates tested to date, expansion has been linear. This would permit estimation of the 30-day expansion by extrapolation from expansion at earlier ages. Opal exhibited no pessimum proportion in the concrete microbar test. Expansion was proportional to the percentage of opal added to an innocuous aggregate., The 12th International Conference on Alkali-Aggregate Reaction in Concrete: 15 October 2004, Beijing, China

The 12th International Conference on Alkali-Aggregate Reaction in Concrete: 15 October 2004, Beijing, China

The differences in the expansive mechanisms of both Alkali Silica (ASR) and Alkali Carbonate Reactive (ACR) rock samples were examined using X-ray diffraction techniques. Reactive aggregates were ground and placed in 1 molar NaOH solution at both 80 and 20°C. Multiple measurements were taken over a 150 day time period. Volume and composition changes were noted. Composition changes were tracked using quantitative Rietveld analysis methods. The observation of a new semi-crystalline tobermorite-like phase common to both ASR and ACR samples raises the possibility of similar mechanisms at work in both processes. However the tobermorite-like phase is less abundant in the alkali silica samples. This new phase only occurred at 80°C, hence the possibility of a temperature induced mechanistic changes is debated., The 12th International Conference on Alkali-Aggregate Reaction in Concrete: 15 October 2004, Beijing, China

During the course of the concrete microbar test the mass changes of the bars were measured at the same time as the lengths. The mass changes of the bars are characteristic of the petrography of the aggregates. Microbars made with 'inert' alumina grinding balls showed continuous mass gain for 50 days, but virtually no expansion. In contrast, microbars containing 50% opal and a non-reactive dolostone exhibited mass loss for about 10 days that was proportional to expansion. Thereafter, the mass loss leveled off. The gel formed by the reaction migrated into the NaOH solution where it precipitated. The greywackes and sandstones, in which microcrystalline quartz is the reactive component, exhibited a mass gain of about 0.4% in the first 8 days followed my mass loss. Only one unaltered volcanic rock, an andesite, was evaluated. It showed mass gain for 15 days but thereafter showed no significant change. Cristobalite is the main reactive component in the andesite. The mass change graphs of the gravels reflected the composition of the major component of the gravel. The damage rating indices (DRI's) were determined at the end of the tests. All the microbars showed extensive fine cracking, without gel, in the cement paste. This pattern of cracking is quite different from that observed in concrete prisms or in cores from field concretes. No correlation was found between the microcrystalline quartz content of many aggregates and expansion in the microbar test. The lack of correlation between expansion in the concrete prism and concrete microbar tests raises serious concerns about the advisability of using the results of the microbar test to evaluate the potential expansivity of aggregates for use in concrete without first confirming the results in a concrete prism test., The 12th International Conference on Alkali-Aggregate Reaction in Concrete: 15 October 2004, Beijing, China

The Concrete Microbar Test is modified after a Chinese test, for alkali-carbonate reactive aggregates, described in 2000. The protocol for the test is essentially the same as for ASTM C 1260, the accelerated mortar bar method except for the size of the bars, the grading of the aggregate, the water to cement ratio and the length of the test. The concrete microbars are 40 by 40 by 160 mm. The aggregate is graded to pass a 12.5 mm sieve and be retained on a 4.75 mm sieve. The water to cement ratio is 0.33. The length of the test is 30 days in 1 M NaOH at 80°C. The test results show that the method is applicable to both alkali-carbonate and alkali-silica reactive aggregates. Moderate correlation was found between the expansions measured in this test at 30 days, and in the concrete prism test (CSA A23.2-14A) at 1 year. When expansions in the concrete prism test and in the concrete microbar test are plotted on a graph the siliceous limestones fall on a separate line from all the other aggregates tested so far including the alkali-carbonate reactive aggregate from Kingston. Some tests were also carried out with some bars measuring 40 by 40 by 300 mm. The longer bars gave, on average, 22% more expansion. Alkali-carbonate reactive aggregates may be distinguished from alkali-silica reactive aggregates in this test by replacing a portion of the portland cement by a supplementary cementing material. The expansions of alkali-silica reactive aggregates are significantly reduced by the presence of the supplementary cementing material but expansion of alkali-carbonate reactive aggregates is largely unaffected. Opal does not appear to exhibit the pessimum effect in this test. It would be premature to establish expansion limits based on the limited number of aggregates tested to date. However, it is tentatively suggested that the expansion limit for siliceous limestones is ~0.13% at 30 days; the limit for all other aggregates is ~0.06%.

This paper summarizes the corrosion results of a 5.3 year study on the corrosion performance of reinforcing steel in concrete slabs containing supplementary cementitious materials and exposed to chlorides. Chloride ions were introduced into the reinforced concrete slabs through a natural migration process, i.e. a ponding solution of 3.4% sodium chloride on the top slab surface of the concrete slab. The concrete mix was designed with a 0.32 water-tocementitious materials ratio (w/cm), containing plain Portland cement and additions of fly ash Class C, fly ash Class F, silica fume and blast furnace slag. Concrete slabs with Portlandcement only and different w/c ratios (0.32, 0.43 and 0.55) were also tested. The thickness of concrete cover to the steel reinforcing bars ranged from 13 mm to 76 mm. Corrosion of the reinforcing steel bars was evaluated using the half-cell potential, linear polarization and AC impedance techniques. The test results indicated that the concrete incorporating fly ash Class C had the best performance with respect to chloride induced corrosion followed by the concrete containing silica fume and the control concrete with w/c of 0.32. In these concrete slabs the corrosion rate of the steel bars was relatively low, even with 13 mm concrete cover. The concretes made with Class F fly ash and blast furnace slag performed better than thePortland cement concretes with w/c of 0.43 and 0.55., NACE Northern Area 2003 Conference, September 14, 2003, Ottawa, Ontario