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[en] The rapid development of industrial production and the availability of underground resources in our republic constantly increases the risk of radon in the building and facilities under construction. The article examines the possibilities of radon penetration into buildings and facilities, the amount of radon in the used building materials, the damage radon causes to human health and the ways of protection from it. Buildings and facilities are exposed to harmful radioactive influences from the environment, the atmosphere and various sources available under the Earth. Among them, the most observed is radon. Since our republic is rich in underground resources, the activity of Radon is higher and poses a serious threat to buildings and installations.
[en] The mass consolidation treatment of azulejos is necessary when ceramic biscuits show signs of disaggregation. Such treatment is often used as a complementary conservation technique to the reestablishment of weakened glaze-ceramic bonds. In this research, two commonly used consolidants (ethyl silicate and acrylic resin) were tested on artisanal ceramic tiles via mass consolidation and the resulting impregnation profiles were evaluated. The results indicated that after consolidation, hard zones frequently formed due to localized consolidant concentration after the polymerization and curing processes. These inhomogeneous hard zones subsequently influenced the results obtained through conventional mechanical strength testing (i.e. flexural and compression), creating a false impression of success. This research demonstrated that by using the Drilling Resistance Measuring System, impregnation characteristics such as penetration depth and distribution of consolidant could be observed that otherwise could not be discerned through the more common testing methods. As such, a more extensive evaluation of consolidation effects was achieved.
[es]En la conservación de los azulejos alterados se utilizan productos con acción consolidante a fin de recuperar la cohesión del cuerpo cerámico disgregado. En este trabajo se investiga el efecto de la consolidación de dos productos muy utilizados en la práctica de la conservación de los azulejos (un silicato de etilo comercial y una resina acrílica), aplicados en un material cerámico artesanal. Los resultados obtenidos indican que pueden producirse zonas con resistencias mayores debido a la concentración local del producto y, a la vez de un material consolidado homogéneo, resulta un material heterogéneo. Por otro lado, la existencia de estas zonas puede conducir a falsos resultados en los ensayos destructivos (resistencia mecánica a la flexión y compresión) utilizados frecuentemente en la evaluación de la acción de consolidación. Se demuestra que mediante el uso de la resistencia a la perforación (DRMS) es posible definir las características, la distribución y el patrón de impregnación, los cuales no pueden ser observadas por los métodos comúnmente utilizados.
[en] Energy needs and concerns in the construction industry are mainly focused on energy savings, characterized by research for new insulation products. Automotive industry, for example, has already overgrown this level of energy performance of their products and fuel economizing is not carried out only through new engine design but also through new aerodynamic lines of vehicles aimed at reducing air resistance. The construction product industry, which, in financial terms, is quite capable to address the issue of energy savings and which benefits from these inventions, has no possibility to interfere in the form of buildings and relations between them. This is something architects and urban planners deal with. This is the subject of this paper, with emphasis on what has been accomplished so far in this regard in the so called developed countries, in comparison with others, where the issues of energy saving are even more difficult to tackle. (author)
[en] Superplasticizers are high range water reducers which are capable of producing high-strength concrete with low permeability. Recently a cement factory in Sindh has launched SPC (Superplasticized Cement) which contains the required amount of superplasticizers. It is needed to investigate its performance compared to that of OPC (Ordinal-Y Portland Cement). This study is framed to optimize various strengths of structural concrete through the use of SPC of the cement factory. In total 288 cubes (6x6x6) were cast and tested for four different compressive strength of concrete (8000, 6000, 5000 and 4000 psi) manufactured with two brands of cement (OPC and SPC) of the cement factory and two different coarse aggregate sizes (40 and 20 mm) at three different curing ages (7,14 and 28 days). The effect on compressive strength of structural concrete was also observed by adopting 5 and 10% reduction in cement content of the superplasticized cement. Results have indicated that structural concrete made with superplasticized cement could give higher compressive strength than that of OPC at all the curing ages, and 10% saving in cement content could be achieved by using superplasticized cement. Structural concrete made with superplasticized cement could attain higher strength in a shorter period of time, and workability of structural concrete could be increased by using SPC. (author)
[en] The new COST action was initiated on the 1st of January 2014 and runs for four years. COST is supported by the EU RTD Framework Program. In the presentation more information on how to participate in the network will be provided. In the presentation the new approach and new initiatives of the NORM4BUILDING network, that has its first meeting here in the DEAD SEA Hotel on the 12-13/02/2014, will be introduced. The NORM4Building materials network will be an open network of researchers. An Advisory Board consisting mainly from NORM processing and construction industries and relevant associations and regulators are invited to work in collaboration with the scientists that will populate the various working groups and the management committee of the new COST action
[en] This book gives descriptions of basic of VE of construction industry including doing away with mannerism, necessity of cost reduction, management method of cost reduction, thinking of idea, target of VE, starting VE activity, technical method of VE of construction industry such as thinking of idea with brainstorming, function trade method, new brainstorming, MM method, morphology analysis and lateral thinking, cases of VE of construction industry.
[en] In a nuclear power plant project, the cost of components and equipments cover 55-60% of the total cost price of the plant. This percentage shows the importance of the national participation to the project. However, one should not ignore the necessity of the special technology, 'know-how' and qualified man power in manufacturing the components and equipments of the nuclear power plant. For countries, planing the utilization of the nuclear power, it is needed to have a preliminary preparation activity. Such an activity, concerning the preliminary preparation phase, should include a feasibility study aiming phase, the survey and assessment of the national manufacturing industries
[en] Construction and demolition waste can be used as a substitution of natural aggregate in mortar and concrete elaboration. A poorer quality of recycled aggregates generally has negative impact on mortar properties. Shrinkage is one of the properties that experiences worse outcome due to the higher absorption of recycled aggregates. This research evaluates the potential shrinkage of mortars elaborated with recycled concrete aggregates both with and without fibres addition, as well as the relation between moisture loss and shrinkage caused by mortar drying process using a capacitive sensor of the authors’ own design. Two different mortar dosages 1:3 and 1:4 and three fiber types: polypropylene fiber, fiberglass and steel fiber, in different proportions were used. Obtained results show that the use of polypropylene fiber improves the recycled mortars performance against shrinkage in 0.2%. Moreover, a clear relation between dry shrinkage and moisture loss was observed.
[es]Los Residuos de Construcción y Demolición pueden ser usados como sustitución de los áridos naturales en la fabricación de morteros y hormigones. La peor calidad de los áridos reciclados empeora de manera general las propiedades de los morteros, siendo la etracción una de las que más se ve afectada. Esta investigación, estudia la retracción de los morteros elaborados con arena reciclada de hormigón con y sin adicción de fibras, así como la relación existente entre la perdida de humedad y la retracción por secado mediante un sensor capacitivo de diseño propio. Se han empleado dos dosificaciones diferentes 1:3 y 1:4 y tres tipos de fibras: polipropileno, vidrio y acero, en distintas proporciones. Los resultados muestran que la adición de fibras de polipropileno en un 0,2% mejora significativamente la retracción en los morteros reciclados. Además, se ha obtenido una relación clara entre la retracción por secado y la perdida de humedad.
[en] In this report, we review the existing concept of construction automation and also survey the state of the art on construction automation and robotic system in domestic and foreign construction industry. On the basis of the result of review and survey, we want to suggest an applicable robotic technology to construction industry and points to be duly considered for activating construction automation. We investigate the state of the art on construction automation and robotic system in domestic and foreign construction industry and also applicable area and direction of domestic construction automation and robotic system. We hope that construction automation and robotic technology, which are improved rapidly nowadays, can contribute to the growth of construction industry
[en] As part of an ongoing effort by the Ministry of Social Affairs and Employment of the Netherlands, a research project is being undertaken to construct a causal model for occupational risk. This model should provide quantitative insight into the causes and consequences of occupational accidents. One of the components of the model is a tool to systematically classify and analyse reports of past accidents. This tool 'Storybuilder' was described in earlier papers. In this paper, Storybuilder is used to analyse the causes of accidents reported in the database of the Dutch Labour Inspectorate involving people working in the construction industry. Conclusions are drawn on measures to reduce the accident probability. Some of these conclusions are contrary to common beliefs in the industry