Entity

Time filter

Source Type


Sanjuan M.A.,Instituto Espanol del Cemento y sus Aplicaciones IECA | Argiz C.,Technical University of Madrid
Materiales de Construccion | Year: 2012

In this paper, the novelties of European standard EN 197-1:2011 which has been aprobed on 6th August, 2011 are presented. The european standard EN 197-1:2011 has been published in the Official Journal of the European Union on 19th June, 2012 (C 176/1). The UNEEN 197-1:2011 will be published in Spain in the Official Journal of Spain (B.O.E.). The date of applicability (DAV) of the standard as a harmonised European standard is on 1st of July, 2012 and the date of the end of the coexistence period is on 1st of July, 2013. The former EN 197-1:2000 has been the first European standard in the field of the Construction Products Directive (CPD) and this first revision include the requirements needed for a common cement to be, in addition, sulphate resisting cement. Therefore, the mandate given by the European Commission to CEN to prepare harmonised standards in the cement field (mandate M114) has been fulfilled. Source


Ortiz S.C.,Instituto Espanol del Cemento y sus Aplicaciones IECA
Carreteras | Year: 2012

This article deals with the principal aspects that affect sustainability in concrete surfacing. These are environmental aspects relating to durability, Life-Cycle Assessment (LCA), savings in volume of materials and light and energy reflectance. Social aspects are analysed relative to safety in driving and safety of the occupants in case of fire in tunnels, a reduction in user inconvenience caused by the maintenance and reinforcement of road surfaces, to savings in the fuel used by travelling vehicles and the new surface finishes for concrete surfacing that equal the roll smoothness and noise abatement convenience of bitumen-mix solutions. Lastly, and to complete the third aspect of sustainability, it evaluates economic aspects from the viewpoint of Life-Cycle Cost Analysis (LCCA), savings in road surface lighting in urban areas and tunnels and its low dependence on the price of oil. Source


Argiz C.,CSIC - Eduardo Torroja Institute for Construction Science | Menendez E.,CSIC - Eduardo Torroja Institute for Construction Science | Sanjuan M.A.,Instituto Espanol del Cemento y sus Aplicaciones IECA
Concrete Repair, Rehabilitation and Retrofitting III - Proceedings of the 3rd International Conference on Concrete Repair, Rehabilitation and Retrofitting, ICCRRR 2012 | Year: 2012

Durability in cold environments of mortars made of ordinary Portland cement, bottom ash and pulverized fuel fly ashes obtained from a coal electrical power stations in Spain have been investigated. This paper presents the experimental investigations carried out to study the effect of use of bottom ash (the coarser material, which falls into furnace bottom in modern large thermal power plants and constitute about 10-15% of total ash content of the coal fed in the boilers) as a replacement of fly ash. The performance of both fly and bottom ashes was investigated in terms of the hydration characteristics and microstructure, when exposed to cold environments. The following compositions were considered: Cement + (fly ash + bottom ash) replacement level up to 35%. The (fly ash + bottom ash) consisted of a bottom ash replacement of 50 and 100% of fly ash in the ashes mix. Use of fly ash beyond 35 percent is allowed in Europe, but the use of bottom ash is presently not permitted as pozzolanic addition in cement nor concrete. The use of coal bottom ash in Portland cement is a new dimension in pozzolanic repairing mortars cement and if applied in standarized Portland cement would revolutionize the cement industry, by economizing the production cost and decreasing the ash content. From the results, the use of bottom ash up to 15 percent as pozzolanic addition in cement repairing mortars is strongly recommended. © 2012 Taylor & Francis Group. Source


Argiz C.,CSIC - Eduardo Torroja Institute for Construction Science | Argiz C.,Technical University of Madrid | Sanjuan M.A.,Instituto Espanol del Cemento y sus Aplicaciones IECA | Munoz-Martialay R.,CSIC - Eduardo Torroja Institute for Construction Science
Materiales de Construccion | Year: 2014

Great durability problems are being found in concrete structures related to the penetrability of aggressive agents through the concrete (ie. chloride penetration, sulphate attack, carbonation, freezing and thawing, and so on). Air permeability coefficient is used as an effective tool to estimate the potential durability of concrete structures due to its direct relation with the microstructure and the moisture content. This paper discusses the effect of the aggregate grading and water/cement ratio on the air permeability coefficient. An aggregate grading with more sand than coarse aggregates has resulted more beneficial from the point of view of concrete air permeability. This fact can be attributed to a denser skeleton formed by the finer aggregates. With fine aggregates, the higher water/cement ratio, the lower air permeability. However, the contrary was found with coarse aggregates. Overall, a temperature increase from 20 °C to 60 °C during preconditioning led to a Dair increase of 40-80%. © 2014 CSIC. Source


Sanjuan M.A.,Instituto Espanol del Cemento y sus Aplicaciones IECA | Pineiro A.,Instituto Espanol del Cemento y sus Aplicaciones IECA | Rodriguez O.,CSIC - National Center for Metallurgical Research
Materiales de Construccion | Year: 2011

Recently, a k-value for ground granulated blast-furnace slag or k-value has been added to the revision of the European standard EN 206-1:2000. The proposed values during the disscusion in the working groups were very different because in most of cases the compressive strength was the only characteristic considered; while only in few cases the concrete durability was taken into account when ground granulated blast-furnace slag is added directly to the mix. Advantages and disadvantages of the k-values found in the literature are discussed in this paper. The final conclusion may be summarised suggesting a logical proposal of addressing to each country the choice of the k-value in function of the concrete application, environment and placing conditions selected according to their own experience. Source

Discover hidden collaborations