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UPCommons - E-prints UPC Universitat Politècnica de Catalunya (59.763 recursos)
E-prints UPC cobreix dues finalitats: per una banda, és el dipòsit institucional de la UPC que recull els articles de revista, les comunicacions de congrés i els reports de recerca generats en les activitats de recerca del personal docent i investigador de la universitat; per l'altra, és una eina que permet accelerar la producció científica, allotjant versions de documents prèvies a la publicació en una revista o a les actes d’un congrés.

Articles de revista

Mostrando recursos 1 - 20 de 130

1. Radiological protection and mechanical properties of concretes with EAF steel slags - González-Ortega, Martha Alejandra; Segura Pérez, Ignacio; Pialarissi Cavalaro, Sergio Henr; Toralles-Carnonari, Berenice; Aguado de Cea, Antonio; Andrello, A. C.
The main objective of this paper is to evaluate the behavior of concretes with EAF slags with structural responsibility exposed to gamma radiation. Six mixes were designed: four concretes made with EAF slags, one conventional concrete, and one heavyweight concrete with barite aggregates. Tests were performed to assess properties such as occluded air, density, compressive strength, modulus of elasticity and gamma rays attenuation (μ). The mechanical properties of concretes with EAF are similar or higher than the measured for conventional concretes and, in all cases, are significantly higher than the obtained for concretes with barite. Although the attenuation coefficients of...

2. Post-handover housing defects: sources and origins - Forcada Matheu, Núria; Macarulla Martí, Marcel; Gangolells Solanellas, Marta; Casals Casanova, Miquel; Fuertes Casals, Alba; Roca Ramon, Xavier
In Spain, the high levels of inexperienced workers and the long chains of subcontracting contribute to the poor quality of dwellings. Althoughthe Ley reguladora de la subcontratación en el Sector de la Construcción (subcontracting law) has established quality measures, the number of customer complaints is still increasing. In this paper, a total of 2,351 posthandover defects derived from four Spanish builders and seven residential developments are classi fi ed according to their source and origin. The research reveals that the most common defects identi fi ed by customers at posthandover were derived from bad workmanship and were related to construction errors and omissions. Typical defects were foundtoincludeincorrectinstallation,appearancedefects,andmissinganitemortaskmainlyrelatedto fi nishingandconsideredtobeminor.No defects were caused by poor...

3. Ensayo de doble punzonamiento para concreto reforzado con fibra: efecto del tamaño y origen de la probeta - Aire, Carlos; Molins i Borrell, Climent; Aguado de Cea, Antonio
Traditionally, to characterize the behavior of reinforced concrete with fiber (CRF) flexural tests are performed on beams. However, in accordance with various studies on FRC, it has been seen different variation coefficients of the order of 20 % for the results of flexural test beams. Recently, it has been developed a new method based on the double punching, called Barcelona test, as an alternative to determine the resistance to the indirect traction of the FRC. It is a test of easy execution over which a cylinder of 150 mm of diameter and 150 mm of height, undergoes double punching test,...

4. Comportamiento resistente de revestimientos de túnel de anillos de dovelas prefabricadas de hormigón - Arnau Delgado, Oriol; Molins i Borrell, Climent
Este artículo presenta los resultados de una investigación llevada a cabo en el ámbito de la respuesta resistente de los revestimientos de túneles a base de anillos de dovelas prefabricadas de hormigón. La investigación arrancó con la realización de una prueba de carga in situ sobre un tramo experimental ubicado dentro de la línea 9 del Metro de Barcelona. Las conclusiones obtenidas sobre su comportamiento permitieron desarrollar modelos de simulación numérica tanto 2D como 3D bien contrastados con los resultados experimentales del ensayo. Esta investigación también incluye el estudio del comportamiento longitudinal del revestimiento, donde se determina hasta qué punto...

5. Predicting on-site environmental impacts of municipal engineering works - Gangolells Solanellas, Marta; Casals Casanova, Miquel; Forcada Matheu, Núria; Macarulla Martí, Marcel
The research findings fill a gap in the body of knowledge by presenting an effective way to evaluate the significance of on-site environmental impacts of municipal engineering works prior to the construction stage. First, 42 on-site environmental impacts of municipal engineering works were identified by means of a process-oriented approach. Then, 46 indicators and their corresponding significance limits were determined on the basis of a statistical analysis of 25 new-build and remodelling municipal engineering projects. In order to ensure the objectivity of the assessment process, direct and indirect indicators were always based on quantitative data from the municipal engineering project...

6. Near-fault isolation of cable-stayed bridges using RNC isolator - Abdel Kareem Moustafa, Mohamed Ismail; Casas Rius, Joan Ramon; Rodellar Benedé, José
This paper investigates the near-fault (NF) seismic performance of a recent isolation system, referred to as Roll-N-Cage (RNC) isolator, considering the cable-stayed Bill Emerson Memorial Bridge in Missouri, USA. Under NF ground motion, the seismic isolation devices might perform poorly because of large isolator displacements caused by long-period large velocity and displacement pulses associated with such strong motion. The RNC isolator is designed to achieve a balance in controlling isolator displacement demands and structural accelerations. It provides in a single unit all the necessary functions of rigid support, horizontal flexibility with enhanced stability and energy dissipation characteristics. Moreover, it is...

7. Influencia de los cerramientos de fábrica en el comportamiento sísmico de edificios de hormigón armado - Moreno González, Rosángel; Bairán García, Jesús Miguel
En España, la mayoría de los edificios de hormigón armado son de forjados reticulares y los cerramientos en estos edificios se suelen materializar con paredes de fábrica que rellenan los marcos entre pilares y forjados. Estas paredes no son portantes y, generalmente, no se considera su contribución resistente ante cargas gravita- torias. No obstante, ante acciones laterales (sismo o viento) la existencia o no de estas paredes puede influir en la respuesta de la estructura. El objetivo de este trabajo es conocer la influencia de la tabiquería en la respuesta sísmica. A partir de planos estructurales reales se define un edificio...

8. The use of concrete in Gaudi's Sagrada Familia - Grima, R; Gómez Serrano, José; Aguado de Cea, Antonio
Despite its unfinished state, the Temple of the Holy Family, or Sagrada Familia, is Antoni Gaudi’s most widely recognized work and one of the most important milestones in the development of Catalan Modernism at the beginning of the twentieth century. This article aims to analyze the role played by concrete in the three different stages of the construction process and to illustrate the uniqueness of the Sagrada Familia. Reinforced concrete started being used in the building’s construction in 1918 to resist the tensions produced in the pinnacles of the facade. From that moment on, mass concrete, reinforced concrete, and prefabricated concrete have...

9. Application of optical fiber distributed sensing to health monitoring of concrete structures - Villalba Herrero, Sergi; Casas Rius, Joan Ramon
The use of Optical Backscatter Reflectometer (OBR) sensors is a promising measurement technology for Structural Health Monitoring (SHM) as it offers the possibility of continuous monitoring of strain and temperature along the fiber. Several applications to materials used in the aeronautical construction have demonstrated the feasibility of such technique. These materials (composites, steel, aluminum) apart from having a smooth surface where the bonding of the sensor is easily carried out, they also have a continuous strain field when subject to external loading and therefore the bonding of the OBR on the material surface is not in danger for high levels...

10. Experimental and analytical study of TRM strengthened brickwork walls under eccentric compressive loading - Bernat Masó, Ernest; Gil Espert, Lluís; Roca Fabregat, Pedro; Escrig Pérez, Christian
The strengthening of load-bearing masonry walls against out-of-plane failure is needed to enhance the life cycle of existing buildings in a sustainable way. In this work, the efficiency of Textile Reinforced Mortar (TRM) for the strengthening of masonry walls is shown by means of an experimental campaign on full scale brick masonry walls. In addition, this campaign has allowed the study of the influence of different mortar and fibre types and the possible benefit of using anchors to improve the connection between the walls and the external reinforcement. The application of TRM has provided an increase of over 100% of...

11. An environmental impact causal model for improving the environmental performance of construction processes - Fuertes Casals, Alba; Casals Casanova, Miquel; Gangolells Solanellas, Marta; Forcada Matheu, Núria; Macarulla Martí, Marcel; Roca Ramon, Xavier
Despite the increasing efforts made by the construction sector to reduce the environmental impact of their processes, construction sites are still a major source of pollution and adverse impacts on the environment. This paper aims to improve the understanding of construction-related environmental impacts by identifying on-site causal factors and associated immediate circumstances during construc- tion processes for residential building projects. Based on the literature and focus group fi ndings, we have developed a construction-related Environmental Impact Causal Model consisting of a process-oriented causal network of thirty-nine environmental impacts, forty- fi ve causal factors and over two hundred causal relationships. It is intended to contribute to a reduction in construction-related environmental impacts on...

12. Gaudi and reinforced concrete in construction - Grima Lopez, Rosa; Aguado de Cea, Antonio; Gómez Serrano, José
The first two decades of the 20th century witnessed the introduction and expansion of reinforced concrete as a building material in Spain. Few years passed between the introduction of the first patents in the most industrialized areas of the Iberian Peninsula and the subsequent generalization of the technique through scientific knowledge obtained in universities. This period coincides almost completely with the professional career of Antoni Gaudí, one of the most famous Catalan architects. This study reports that Gaudí had contact with this new material and discusses the transition he made from the traditional construction methods to the use of reinforced...

13. Evolution of the formwork used in the temple of the Sagrada Familia - Gómez Serrano, José; Espel, R; Grima, R; Burry, Mc; Aguado de Cea, Antonio
The Sagrada Família is Gaudi's unfinished work, to which he exclusively dedicated his last years of life. Even though he only got to build a small part of the total, he defined the rest through models and photographs. Gaudi's design for the inside of the Temple was based on a new geometric architecture that made extensive use of ruled surfaces (paraboloids, hyperboloids, ellipsoids), opening a new field which later architects have followed. The following article aims at showing the construction complexity of these structures, especially in relation to the set-up of their formwork. The vaults, which cover the naves at...

14. Reactions of fly ash with calcium aluminate cement and calcium sulphate - Fernández Carrasco, Lucía; Vázquez Ramonich, Enric
The hydration processes in the ternary system fly ash/calcium aluminate cement/calcium sulphate (FA/CAC/C$) at 20 °C were investigated; six compositions from the ternary system FA/CAC/C$ were selected for this study. The nature of the reaction products in these pastes were analysed by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). At four days reaction time, the main hydration reaction product in these pastes was ettringite and the samples with major initial CAC presented minor ettringite but calcium aluminates hydrates. The amount of ettringite developed in the systems has no direct relation with the initial components.

15. Proyecto y construccion del cierre del ábside de la Sagrada Familia - Buxadé, Carles; Gómez Serrano, José; Espel, Ramon; Grima, Rosa; Buxadé, Agata; Ferrando, Ramon; Aguado de Cea, Antonio
Peer Reviewed

16. New analytical model to generalize the Barcelona Test using axial displacement - Pujadas Álvarez, Pablo; Blanco Álvarez, Ana; Pialarissi Cavalaro, Sergio Henr; Fuente Antequera, Albert de la; Aguado de Cea, Antonio
The Barcelona Test has proved to be very suitable for the systematic control of the tensile properties of Fibre Reinforced Concrete (FRC). Nevertheless, the need to measure the total circumferential opening displacement (TCOD) of the specimen entails the use of an expensive circumferential extensometer. In order to simplify the test, studies from the literature propose the use of the axial displacement of the press (δ) instead of the TCOD, obtaining empirical equations to correlate the energy estimated with both measurements. However, these equations are only valid for δ ranging from 1 to 4 mm and were adjusted based on the...

17. Recycling silicon solar cell waste in cement-based systems - Fernández Carrasco, Lucía; Ferrer, R.; Aponte Hernández, Diego Fernando; Fernández, P.
This is a study of the recycling of crystalline solar cells by incorporating them in cement matrices. The hydration process of a mixture of calcium aluminate cement (CAC) and solar photovoltaic cell waste was researched and analyzed. The nature of the hydration products of various compositions of these mixtures was evaluated at a temperature of 20 1C by analyzing the samples through X-ray diffraction, infrared spectroscopy and scanning electron microscopy. The total porosity and mechanical strength development of these materials were also determined. It was revealed that the presence of a solar cell residue of up to 5% in the...

18. Model for enhancing integrated identification, assessment, and operational control of on-site environmental impacts and health and safety risks in construction firms - Gangolells Solanellas, Marta; Casals Casanova, Miquel; Forcada Matheu, Núria; Fuertes Casals, Alba; Roca Ramon, Xavier
Certifiable management-system standards apply similar management techniques and principles, but each system still tends to have a separate structure in construction companies. Research and practice have demonstrated that management tasks may be duplicated when standards are implemented in parallel. Consequently, integrated management systems are strongly advocated. However, existing literature demonstrates that the integration of planning and control instruments involves a high level of uncertainty. This paper presents an innovative model to enhance the integration of environmental- and health and safety – management systems in construction companies, focusing on the subsystems for identifying, assessing, and operationally controlling environmental aspects and health and safety hazards and using risk as...

19. Diseño de mezclas de hormigón reciclado mediante el método Volumen de Mortero Equivalente (EMV): Validación bajo el contexto español y su adaptación al método de diseño de Bolomey - Jiménez Fernández, Cristian Gonzalo; Vázquez Ramonich, Enric; Barra Bizinotto, Marilda; Valls del Barrio, Susanna; Aponte Hernández, Diego Fernando
El nuevo método para el diseño de hormigón con árido reciclado (HAR) es usado para comprobar su posibilidad de uso bajo el contexto español. Primeramente, se realiza una extensa campaña experimental, para analizar las posibilidades de su aplicación, usando dos áridos reciclados de hormigón (ARH) españoles. En la segunda etapa se elabora una adaptación del método a la metodología propuesta por Bolomey (1), con 20% de reemplazo en peso de árido grueso natural (AN) por ARH, para así cumplir con las recomendaciones estipuladas en la Instrucción de Hormigón Estructural (EHE 2008). Para determinar y analizar las propiedades del hormigón, se llevaron a...

20. Design of macro-synthetic fibre reinforced concrete pipes - Fuente Antequera, Albert de la; Campos Escariz, Renata; Domingues de Figueiredo, Antonio; Aguado de Cea, Antonio
This paper presents an experimental campaign in which concrete pipes were manufactured using plastic fibres as the sole reinforcement material. In this regard, it has been demonstrated that the use of plastic fibres is compatible with pipe production systems, and that, when subjected to the crushing test (CT), plastic fibre reinforced pipes yield strength classes that are attractive in terms of the growth of this material in the concrete pipe industry. Moreover, the results obtained from both the characterisation of the material and the mechanical behaviour of the pipes have been used to verify that the Model for the Analysis of...

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