Recursos de colección

Archivo Digital UPM (106.784 recursos)

This is an institutional repository providing access to the research output of the institution. Primarily contains thesis.

Materia = Materiales

Mostrando recursos 1 - 20 de 1.011

  1. Medida del deterioro del hormigón sometido a hielo-deshielo con bandas extensométricas

    Romero, Hector; Casati Calzada, Maria Jesus; Galvez Ruiz, Jaime Carlos
    Los daños producidos por los ciclos de hielo deshielo en el hormigón llegan hasta un 13% del total de los daños. Estos daños pueden ser internos y externos, y se manifiestan en la disminución del módulo de elasticidad dinámico y la aparición de fisuras, y el descascarillamiento superficial, respectivamente. La mayoría de los ensayos normalizados para la evaluación de la resistencia del hormigón a los efectos del H-D se basan en la medida del daño externo. Estas medidas requieren parar el ensayo y manipular las probetas fuera de la cámara climática. En este trabajo se propone el uso de medidas...

  2. Aplicación de recubrimientos de carbono DLC sobre Poli (ácido láctico) mediante Sputtering Magnetrón. Transformaciones en el plástico y efecto sobre algunas propiedades.

    Blázquez Luengo, Fernando
    Desde finales del s. XX hasta el día de hoy, la demanda de polímeros sintéticos continua creciendo para multitud de aplicaciones, entre otras la fabricación de envases. La mayoría de estos polímeros son poliolefinas, y una gran cantidad de éstos acaba como productos de desecho. La problemática que conlleva estos plásticos una vez desechados, es que son inmunes a la mayoría de los procesos de degradación naturales, por lo que suponen un importante contaminante del medio ambiente. Debido a este contexto, los bioplásticos tienen cada día un papel más importante como reemplazo de estos polímeros no biodegradables en muchas aplicaciones....

  3. Designing digital cooperation work spaces for students, for group collaboration and virtual collaboration

    Salaberri Merino, Aitzol; Alcázar Márquez, Alicia; Nieuwborg, Alexander; Herpin, Hugo; Pouppeville, Thibault
    The ground floor of P52 needs to be redesigned in order to make it more visible and attractive. This report explains the process that a group of international students has gone through during the realization of this task. Finally the report explains the final design proposal and the reasons to led to each decision that was made.

  4. Estudio de la maquinabilidad de aleaciones de aluminio-cobre

    Sánchez Almirón, Borja; Aguirre Cebrian, Maria Vega; Calvo Narvaez, Felix; González Requena, Ignacio; Sanz Lobera, Alfredo
    El cometido principal es establecer una metodología para analizar y evaluar la maquinabilidad de una aleación aluminio-cobre mecanizada en torno utilizando los recursos disponibles en los laboratorios de materiales y producción. El estudio se realizó mediante la medida del caudal de viruta, el dimensionado de la herramienta durante el proceso y su análisis microscópico. También se estudió el posible desgaste de la herramienta y qué factores han podido incrementar o disminuir dicho valor. Se han mecanizado ocho barras de una aleación 2030 T4 con dos herramientas de corte idénticas de carburo de wolframio. Esto permite usar cada filo de corte...

  5. Cylindrical shed construction: the shell roof on the Jamin factory at Oosterhout, Netherlands

    García García, Rafael; Valcarce Labrador, María Teresa
    The paper provides an overview of cylindrical shed reinforced concrete shells, a type of construction used primarily in industrial buildings. Like other types of shells, most cylindrical sheds were built between the end of World War II and the early nineteen sixties. The article reviews their characteristics and construction parameters based on contemporary studies and briefly documents some of the most prominent structures. The final chapter contains a detailed analysis of the design and construction of what, to the authors’ knowledge, is the largest such shell ever erected. Built for the Jamin factory at Oosterhout, Netherlands, this shed was the...

  6. Enhanced ultrafiltration PES membranes doped with mesostructured functionalized silica particles.

    Martín, Antonio; Arsuaga, Jesús M.; Roldán, Nuria; De Abajo, Javier; Martínez Blanco, Ana; Sotto, Arcadio
    Novel hybrid ultrafiltration membranes have been prepared by incorporation of mesostructured functionalized silica particles in polyethersulfone. Physico-chemical characterization of synthesized materials was accomplished to determine the textural and structural properties of particles by nitrogen adsorption?desorption and TEM. A successful functionalization of silica with amine and carboxylic groups was confirmed by means of MAS-NMR. Membrane surface morphology was studied in terms of pore size distribution, porosity and hydrophilicity, suggesting a great influence of mesostructured silica incorporation in polyethersulfone on the polymer matrix configuration. Membrane functions were significantly improved as a result of a considerable increase of water permeation without affecting negatively...

  7. Diferencias de comportamiento entre un hormigón convencional y un hormigón ligero = Behaviour differences between a normal concrete and a lightweight concrete

    Olmedo Zazo, Fernando Israel; Mateos Delso, Isabel; Díaz Majano, F. Javier; González García, María de las Nieves; Cobo Escamilla, Alfonso
    Resulta paradójico que a pesar de las enormes ventajas que supone en muchas aplicaciones de construcción el empleo del hormigón ligero estructural (HLE) frente a un hormigón convencional (HC), su uso todavía no se haya generalizado. Muy posiblemente, el desconocimiento de su comportamiento físico y mecánico con tribuye de forma decisiva a la utilización de un HC en muchas ocasiones en las que su sustitución por HLE sería totalmente competitivo y ventajoso. Este trabajo pretende ampliar el conocimiento del comportamiento del HLE para contribuir a su utilización en todas las situaciones en donde su empleo supone una clara ventaja frente al...

  8. A closer look to the mechanical behavior of the oxide layer in concrete reinforcement corrosion

    Sanz Merino, Beatriz; Planas Rosselló, Jaime; Sancho Aznal, José María
    Results of concrete cracking in accelerated corrosion tests are presented for concrete prisms cast around a smooth steel tube simulating a rebar. Special instruments were used to measure the variation of inner diameter and volume of the tube while recording the width of the main crack by classical means. Numerical simulations of the tests with a model that reproduces the volumetric expansion of the oxide and the associated concrete cracking were used to narrow the uncertainties in the mechanical properties of the oxide layer with satisfactory results.

  9. Estudio de un nuevo método de adición de microsílice en materiales de base cemento

    Francisco Monción, Andrés Ismael
    El objetivo general de este trabajo de fin de máster es el estudio de un nuevo método de adición de microsílice denominado método de electrodeposición (DE), que consiste en la deposición de las adiciones sobre el cemento mediante un procedimiento electrostático que consigue una optimización de la dispersión de las partículas de adición sobre la superficie del cemento. La eficacia de este método se compara con el método tradicional de homogenización manual (MA). Para este fin se evalúan las propiedades mecánicas y microestructurales de pasta de cemento y mortero. Se analizan diferentes porcentajes de adición de microsílice de distinta procedencia...

  10. Estudio de inestabilidad en sólidos con ablandamiento por deformación

    Santos Merán, Carlos Augusto de los

  11. Induction of through-thickness compressive residual stress fields in thin Al2024- T351 plates by laser shock processing

    Ocaña Moreno, José Luis; Correa Guinea, Carlos; Porro González, Juan Antonio; Díaz Muñoz, Marcos; Ruiz de Lara de Luis, Leonardo; Peral Jiménez, David
    Purpose - With the aid of the calculational system developed by the authors, the analysis of the problem of laser shock processing (LSP) treatment for induction of residual stress (RS) fields for fatigue life enhancement in relatively thin sheets in a way compatible with reduced overall workpiece deformation due to spring-back self-equilibration has been envisaged. Numerical results directly tested against experimental results have been obtained confirming the critical influence of the laser energy and irradiation geometry parameters. The paper aims to discuss these issues. Design/methodology/approach - Plane rectangular specimens (160mm×100mm×2mm) of Al-cladded (-80µm) Al2024-T351 were considered both for LSP experimental...

  12. Manufacturing and Analysis of Bioactiva Glass Fiber, and its Application in Biomedical Engineering

    Roca Puertas, Sergi
    En el presente trabajo de investigación, se pretende hacer un estudio de como varían las pro-piedades térmicas, mecánicas y químicas de las fibras de vidrio bioactivo de fosfato en función de su composición. A rasgos generales se puede decir que en lo que consiste el trabajo es en la fabricación de vidrio bioactivo, extrusión de fibras e inmersión de las mismas en un tampón químico llamado SBF (Simulated Body Fluid). Luego se procede al análisis de los resultados, para ello se realizaron diversos estudios en los que se incluyen la Espectroscopia de Absorción Atómica (AAS), Espectroscopia en Transformada de Fourier...

  13. Caracterización mecánica experimental de un hormigón ligero estructural = Experimental mechanical characterisation of a structural lightweight aggregate concrete

    Olmedo Zazo, Fernando Israel; Cobo Escamilla, Alfonso; Díaz, Borja; Navarro Gabaldón, Francisco; Vidal Mesa, María Ángeles
    The self load of the structure is usually similar even bigger than any other load load which a structure carries. Due to this fact a number of structure are inefficient. The replacement in concrete of normal aggregate by lightweight aggregate reaches a markedly reduction of the concrete weight. The mechanical behavior of a lightweight aggregate concrete is analyzed in this paper. A number of tests have been done at different ages. These results have been compared with the predicted mechanical values of some regulation

  14. Estudio experimental del comportamiento a compresión de hormigones autocompactantes reforzados con fibras de acero = Experimental study of performance self-compacting concrete reinforced with steel fibers

    Sánchez Pérez, José Luis; Cobo Escamilla, Alfonso; Díaz, Borja; Mateos Delso, Isabel
    Self-compacting steel fibers reinforced concrete simultaneously has the advantages of self-compacting concrete and reinforced with fibers. A material of high performance in their laying on site, toughness and ductility is achieved. This paper has studied the mechanical behavior of a self-compacting concrete reinforced with steel fibers. Have been made compression tests, as well as non-destructive testing (measuring the speed of ultrasound and sclerometer test). The results show the variation of the response of concrete with time, the difference with the traditional concrete and the feasibility of using non-destructive techniques for controlling this type of concrete.

  15. Avances en el uso de metacaolín para la mejora de las propiedades de los morteros de cemento tipo portland

    García López de la Osa, Gregorio; González Cortina, Mariano; Rio Merino, Mercedes del
    El presente trabajo resume los avances conseguidos hasta el momento en la búsqueda de la mejora de las propiedades de los morteros de cemento tipo portland adicionados con metacaolín, que forman parte de fábricas constituidas por estos morteros y ladrillos cerámicos.

  16. Influence of Titanium on the Micro and Macrostructure of Hypoeutectic Cast Iron

    García-Caro Martín, Paula
    Influence of Titanium on the Micro and Macrostructure of Hypoeutectic Cast Iron is a Master Thesis carried out by Paula García-Caro Martín, student of the Escuela Técnica Superior de Ingenieros Industriales de la Universidad Politécnica de Madrid (Spain), at the School of Engineering of Jönköping University under the Erasmus program “SMP-Student Mobility for Traineeships”, during 11 months. The goal of this work is to study the Titanium effects on hypoeutectic grey iron. The first part of the work consists of a brief introduction on the basic necessary concepts to understand the solidification of cast iron and also a short summary of...

  17. Inclusion complex between beta-cyclodextrin and phenylphosphonicdiamide as novel bio-based flame retardant to epoxy: Inclusion behavior, characterization and flammability

    Zhao, Xiaomin; Xiao, Dan; Picón Alonso, Juan; Wang, De-Yi
    The aim of this work was to study the impact of inclusion complex (IC) between β-cyclodextrin (β-CD) and N,N′- diamyl-p-phenylphosphonicdiamide (P-MA) on the thermal stability and flame retardancy of epoxy resin (EP). IC was synthesized via inclusion process and characterized by 1H nuclear magnetic resonance (NMR), X-ray diffraction (XRD), differential scanning calorimeter (DSC) and scanning electronmicroscopy with X-ray microanalysis (SEM-EDS). 1H NMR was used to identify the mole ratio of β-CD/P-MA in IC, shown that theirmole ratiowas 1:0.5. The inclusion complex (IC)was proposed to be a char promoter in EP via a combination of the properties of b-CD and P-MA during...

  18. New Superefficiently Flame-Retardant Bioplastic Poly(lactic acid): Flammability, Thermal Decomposition Behavior, and Tensile Properties

    Zhao, Xiaomin; Reyes Guerrero, Francisco; Llorca Martinez, Francisco Javier; Wang, De-Yi
    In this study, a superefficiently flame-retardant bioplastic poly(lactic acid) was developed by incorporating gas–solid biphase flame-retardant N,N′-diallyl-P-phenylphosphonicdiamide (P-AA), into PLA matrix. The flame retardancy of PLA/P-AA was investigated by limiting oxygen index (LOI), vertical burning test (UL94), and cone calorimeter test. Surprisingly, it was noted that only 0.5 wt % loading of P-AA increased LOI value of PLA from 20.5 to 28.4 and passed UL 94 V-0 rating at 3.2 mm thickness. In order to understand the effect of P-AA on the thermal decomposition behavior of PLA, a comprehensive study was investigated in this paper, including (i) adopting modified Coats–Redfern...

  19. Effect of N, N'-diallyl-phenylphosphoricdiamide on ease of ignition, thermal decomposition behavior and mechanical properties of poly (lactic acid)

    Zhao, Xiaomin; Juan, Sergio de; Reyes Guerrero, Francisco; Li, Zhi; Llorca Martinez, Francisco Javier
    In this study, a novel poly (lactic acid) (PLA) composite with low flammability based on N,N′-diallyl-phenylphosphoricdiamide (PO-AA) and PLA was developed via traditional melt compounding. PO-AA exhibited high efficiency on reducing the ease of ignition of PLA without scarifying the mechanical and thermal properties of PLA. Only 1 wt% of PO-AA containing PLA composite passed V-0 rating with 3.2 mm (thickness of the specimen), while 2 wt% of PO-AA addition made PLA passed V-0 rating with thickness of 1.6 mm. The improvement also performed on increased limiting oxygen index (LOI) of PLA composites. The melting and crystallization behavior of PLA...

  20. Improved cement mortars by addition of carbonated fly ash from solid waste incineration

    López Zaldívar, Óscar; Mayor Lobo, Pablo Luis; Fernández Martínez, Francisco; Hernández Olivares, Francisco
    This article presents the results of a research developing high performance cement mortars with the addition of municipal solid waste incineration fly ash (MSWIFA) stabilized as insoluble carbonates. The encapsulation of hazardous wastes in mortar matrixes has also been achieved. The ashes present high concentrations of chlorides, Zn and Pb. A stabilization process with NaHCO3 has been developed reducing 99% the content of chlorides. Developed mortars replace 10% per weight of the aggregates by treated MSWIFA. Physical/mechanical properties of these mortars have been studied. Presence of Zn, Pb, Cu and Cd has been also analyzed confirming that leaching of these...

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