UPCommons - E-prints UPC Universitat Politècnica de Catalunya
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 133
Plastic fibres as the only reinforcement for flat suspended slabs: Experimental investigation and numerical simulation - Pujadas Álvarez, Pablo; Blanco Álvarez, Ana; Pialarissi Cavalaro, Sergio Henrique; Aguado de Cea, Antonio
This paper focuses on the study of the structural response of hyperstatic concrete flat suspended slabs reinforced only with structural plastic macro-fibres. First, the experimental program is described and then the results obtained are presented. The slabs tested maintained a high load level after cracking showing a ductile behaviour with great stress redistribution capacity. Next, the tests were simulated by means of a finite element software with constitutive models according to the specifications of RILEM and the Spanish Structural Concrete Code (EHE). The numerical results in terms of load/mid-span deflection were compared with the experimental results. The predictions provided by...
Collapse of a precast concrete beam for a light roof: importance of elastomeric bearing pads in the element’s stability - Bairán García, Jesús Miguel; Cladera Bohigas, Antoni
The importance of second order effects has been widely studied in slender concrete structures subjected to compressive stresses, although their effects are not generally taken into account in other fields of structural engineering; this is the case of the overall stability of structures flexible supports, as elastomeric bearing pads. In this paper, the collapse in construction of a 24.9 m span precast concrete Y-beam for the light roof of a sports hall is studied. The roof consisted of a series of these beams simply supported at each end by plain neoprene bearing pads. After a worker had climbed up to...
Experimental and numerical analysis of bending-buckling mixed failure of brickwork walls - Bernat Masó, Ernest; Gil Espert, Lluís; Roca Fabregat, Pedro; Sandoval, Cristian
The eccentric in-plane loading of masonry walls involves complex bending performance that includes second-order effects. In this work, a bidimensional (2D) simplified micro-model for the analysis of this type of failure is developed. An experimental investigation based on 20 tests of full-scale unreinforced masonry walls is performed. The tests are characterised by slenderness and load eccentricity. The analytical methods of Eurocode-6 and ACI-530 are compared with experimental data from the present investigation, other experimental results available in the literature and simulation results from the numerical model.
Radiological protection and mechanical properties of concretes with EAF steel slags - González-Ortega, Martha Alejandra; Segura Pérez, Ignacio; Pialarissi Cavalaro, Sergio Henrique; 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...
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.
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
ed according to their source and origin. The research reveals that the most common defects identi
by customers at posthandover were derived from bad workmanship and were related to construction errors and omissions. Typical defects were
defects were caused by poor...
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,...
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...
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...
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...
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...
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...
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...
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...
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
ndings, we have
developed a construction-related Environmental Impact Causal Model consisting of a process-oriented
causal network of thirty-nine environmental impacts, forty-
ve causal factors and over two hundred
causal relationships. It is intended to contribute to a reduction in construction-related environmental
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...
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...
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.
New analytical model to generalize the Barcelona Test using axial displacement - Pujadas Álvarez, Pablo; Blanco Álvarez, Ana; Pialarissi Cavalaro, Sergio Henrique; 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...
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...