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This paper presents results from investigations on the long-term influence of concrete surface and crack orientation on ingress in cracks. Five reinforced concrete structures from Norway exposed to either de-icing salts or seawater have been investigated. Concrete cores were taken with and without cracks from surfaces with vertical and horizontal orientation. Carbonation in cracks was found on all de-iced structures, and a crack on a completely horizontal surface appeared to facilitate chloride ingress. Ingress of substances from seawater was found in all cracks from marine exposure. However, the impact of cracks on chloride ingress was unclear. Horizontal cracks on vertical surfaces appeared to facilitate self-healing. © Article authors. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivs licens. (http://creaticecommons.org/licenses/by.nc-nd/3.0/).

Bleeding, a type of static segregation derives from density difference of concrete ingredients in fresh state. Due to having this difference higher than normal weight counterparts, heavyweight concrete is more susceptible to bleeding, thus, this type of concrete is commonly produced in low slump values. In order to give a response to advances and demands in concrete technology, heavyweight concrete mixtures with high slump values were designed at various mixture characteristics, and their bleeding characteristics were researched in the study. For this purpose, totally, thirty-five concrete mixtures with ?150 mm slump values were produced by using common cement replacement materials (silica fume and fly ash), viscosity modifier, and various water/binder ratios at two binder dosages. The mixtures showed excessive bleeding capacities ranged from 0 to 11.7% and bleeding rates ranged from 0 to 5.1 kg/m2/h. Silica fume was found as the most effective admixture for reducing or elimination of the bleeding. Bleeding time generally shorten at high binder content and at high water/binder ratio. It was observed that the bleeding adversely affects the hardened characteristics of heavyweight concrete mixtures. © 2018 Elsevier Ltd

The European Union low-carbon strategy includes a range of complementary policies. Potential interactions between instruments and different timing of their implementation can influence the cost and likelihood of achieving the targets. We test the interactions between the three main pillars of the European Union strategy through a dynamic Computable General Equilibrium model (GDynEP) with a time horizon of 2050. Main results are: i) going for the unilateral European Union carbon mitigation target without any complementary technological policy will produce large economic losses; ii) by investing in clean energy technologies (energy efficiency and renewable energy) with a carbon tax revenue recycling mechanism, these losses will decrease substantially; iii) when complementary clean energy technology policies are implemented, the optimal timing of binding targets changes; iv) the higher the public support to clean energy technologies, the larger the economic gains in early adoption of challenging abatement targets. © 2018 Elsevier Ltd We acknowledge financial support received by the EU D.G. Research (research project “CECILIA2050 — Choosing efficient combinations of policy instruments for low-carbon development and innovation to achieve Europe

The effect of the concentration of three hydrocolloids: CMC, guar gum and xanthan gum on the syneresis, rheological features and sensory consistency of the artichoke sauce (Cynara scolymus L.) Imperial Star variety was studied. The syneresis was determined by the water loss by centrifugation, the rheological features of the artichoke sauce was determined using a Brookfield RVDV – III model rheometer and finally, the sensory consistency was determined by measuring the degree of satisfaction with hedonic scale of nine points. A simplex lattice design blends with centroid expanded under the response surface methodology was applied to establish the effect of the concentration of hydrocolloid on syneresis, rheological features and sensory consistency. In all treatments, the apparent viscosity decreased with shear rate demonstrating a “non Newtonian” behavior of “general plastic” type with an “n” value less than 1 and an initial shear stress. The flow behavior index “n” was in the range of 0.0856 and 0.3131 (n < 1) and the consistency index “k” in the range of 84.55 y 167.80 Pa.sn , the initial shear stress was in the range of 9,10 y 13,51 Pa and consistency sensory presented score of “like” to “like slightly”. Finally, the hydrocolloid mixture was optimized over the area of feasible formulation. With the optimal mixture, corresponding to 0.28% CMC, 0.13% guar gum and 0.59% xanthan gum is expected to obtain a 0.089% of syneresis and a rating of 6 in terms of sensory consistency. Se investigó el efecto de la concentración de tres hidrocoloides: CMC, goma guar y goma xantana, y sus mezclas en la sinéresis, características reológicas y consistencia sensorial de salsa de alcachofa (Cynara scolymus L.) variedad Imperial Star. La sinéresis se determinó mediante la pérdida de agua por centrifugación; las características reológicas de la salsa de alcachofa utilizando un reómetro marca Brookfield modelo RVDV – III y finalmente, la consistencia sensorial, mediante una escala hedónica de nueve puntos. Se aplicó un diseño de mezclas simplex reticular con centroide ampliado bajo la metodología de superficie de respuesta para establecer el efecto de la concentración de hidrocoloides sobre la sinéresis, características reológicas y consistencia sensorial. En todos los tratamientos, la viscosidad aparente disminuyó con la velocidad de cizalla demostrando un comportamiento “no newtoniano” de tipo “plástico general” con un valor “n” menor a 1 y un esfuerzo de corte inicial. El índice reológico estuvo en el rango de 0,0856 y 0,3131 (n < 1), el índice de consistencia “k” en el rango de 84,55 y 167,80 Pa.sn , esfuerzo de corte inicial en el rango de 9,10 y 13,51Pa y la consistencia sensorial presentó calificaciones de “me gusta” a “me gusta ligeramente”. Finalmente, se optimizó la mezcla de hidrocoloides sobre la zona de formulación factible. Con la mezcla óptima, correspondiente a: 0,28% CMC; 0,13% goma guar y 0,59% goma xantana se espera obtener una sinéresis de 0,089% y una calificación de 6 “me gusta ligeramente” en cuanto a la consistencia sensorial.

[EN] This article assesses the effect of mix design parameters on the compressive strength and thermal performance of alkali silicate-activated blends of metakaolin (MK) and granulated blast furnace slag (GBFS). A strong interrelationship between the effects of activator composition and the GBFS/(GBFS + MK) ratio is identified through statistical analysis of compressive strength data. Pastes formulated with higher SiO 2/Al 2O 3 molar ratios show improvements in mechanical strength with increasing GBFS addition, associated with the formation of a structure comprising coexisting aluminosilicate 'geopolymer' gel and Ca-rich Al-substituted silicate hydrate (C-(A)-S-H) reaction products. The inclusion of GBFS in MK-based geopolymers seems also to improve their performance when exposed to high temperatures, as higher residual compressive strengths are reported for these mixtures compared to solely MK-based systems. Only slight differences in shrinkage behaviour are observed at temperatures of up to 600 °C with the inclusion of GBFS; however, slag-blended pastes exhibit enhanced stability at temperatures exceeding 800 °C, as no variation in the compressive strength and no additional shrinkage are identified. These results suggest that nanostructural modifications are induced in the gel by the inclusion of GBFS into MK-based geopolymers, improving the overall performance of these materials. © 2011 Springer Science+Business Media, LLC., This study was sponsored by Universidad del Valle (Colombia), Instituto Colombiano para el Desarrollo de la Ciencia y Tecnologia "Francisco Jose de Caldas" (COLCIENCIAS) and the Center of Excellence of Novel Materials (CENM). The participation of JLP was funded by the Australian Research Council (ARC), including partial funding through the Particulate Fluids Processing Centre, a Special Research Centre of the ARC.

The rationale behind an asphalt mix design is optimizing the binder content for the desired aggregate gradation to satisfy the specified volumetric and strength requirements. The designed asphalt mix should be durable and cost effective. The mechanical behavior of a designed asphalt mix is affected by the traffic loading and climatic variations. To improve the mechanical properties of asphalt mixes, additives are added to the base asphalt binder. These binders are called modified asphalt binders. The objectives of the present study are to compare the performance of asphalt mixes with different binders by two different mix design methods and to optimize the asphalt binder type to achieve the desired performance. Two methods of mix design namely, Marshall and Superpave mix design methods are considered. The performances of asphalt mixes viz., tensile strength, moisture damage, densification and rutting resistance were compared. The results indicated a statistically significant difference in the optimum asphalt binder content from the two mix design methods. The Marshall method of asphalt mix design is found to yield lower optimal asphalt binder content when compared to the Superpave method of mix design. The moisture susceptibility and construction densification index of asphalt mixes designed using Superpave method were found to be significantly lower than that of the mixes designed by Marshall method. Optimization using a Mixed Integer Linear Program (MILP) indicated that the polymer modified asphalt binder outperforms the requirements of engineering properties when compared to other commercial binders used in the study. � 2010 Elsevier Ltd. All rights reserved.

In spite of all its advantages, the time factor is one major cause for the construction engineers to go for proper mix designs. In Indian conditions, it is often not possible to get materials from the same source throughout the construction stage. Each time when the materials (especially cement) changes, spending 45-60 days for a fresh design is often impractical. This demands a lookout for other options. The method developed by the national council for building materials [1] based on accelerated curing of concrete (IS 9013:1978, reaffirmed in 2004) is apparently an exciting solution to this problem as it can produce the results in two to three days. An inquest is made here on the reliability of this method on practical problems.

The equi-viscous temperature range of asphalt has long been used in establishing the mixing temperature for mix designs and field production of hot mix asphalt (HMA). However, this method considers only binder viscosity to determine the mixing temperatures of the aggregate and asphalt. It is well known that depending on the gradation of aggregate and the type of plant and the mixing time. The appropriate mixing temperature for the proper coating may be lower than that of the viscosity based method. The excessive temperature causes the possible performance problems related to the hardening of the asphalt binder and increases the energy consumption, the gas emissions and fumes. In this study, a new method for the determination of asphalt-aggregate mixing temperature which considers the mixture properties was introduced to asphalt industry. The mixing temperatures of different nine mixtures were determined by both conventional and the proposed method. The effects of the nominal maximum aggregate size (NMAS), crushed coarse aggregate ratio (CCAR), the type of gradation, and the grade of binder on the mixing temperature were evaluated with an experimental study. Results show that decreasing NMAS, CCAR and increasing the grade of binder decreased the mixing temperature which is needed for proper coating. In addition, results showed that as going away from restricted zone of the Superpave gradation, the needed temperature to coat the aggregates decreased. The proposed method resulted in lower temperatures comparing to the conventional method on an average of 13°C. This means a possible energy saving of 14.3 x 10 9 kcal or 1362000 kg of crude oil in a year in Turkey. As a result, the new method is recommended due to not only the saving in energy but also decreasing the gas emissions and fume, and possible performance benefits. © Sila Science.