Ingeniería Civil y Mecánica
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Item Caracterización del comportamiento frente al fuego de la madera con recubrimiento de barniz utilizados en obra civil(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2025-02) Yugcha Lema, Jonathan Andrés; Viscaíno Cuzco, Mayra AlexandraThe use of wood coated with varnishes for flooring and wall coverings is widespread in the construction industry. However, its behavior in the event of a fire has been little studied, raising significant questions about its performance in fire scenarios. This research aims to characterize the behavior of Mascarey wood under fire conditions, considering its physical, mechanical, and thermal conductivity properties in three states: natural, coated with Monto brand high-gloss varnish, and coated with Condor brand Espengloss floor lacquer. Physical properties such as color and density were evaluated according to ASTM D 1535 and ASTM D2395 standards, respectively. Mechanical properties were assessed through parallel compression, perpendicular compression, and hardness tests, following the procedure described in ASTM 143-94. Additionally, a fire reaction test was conducted according to the NTE INEN ISO 11925 – 2 standards, using 18 Mascarey wood specimens with a thickness of 20 mm subjected to direct flame exposure, both on the edge and surface. The results indicate that the density of Mascarey wood increased by 4.5 percent when treated with coatings compared to its natural state. Regarding mechanical properties, specimens coated with Monto varnish showed a decrease in parallel and perpendicular to fiber compression resistance, with values of 47.97 N/mm2 and 13.71 N/mm2, respectively. Conversely, specimens coated with Espengloss lacquer showed an increase in these properties, reaching values of 50.03 N/mm2 in parallel compression and 15.06 N/mm2 in perpendicular compression, compared to natural specimens, which recorded values of 48.33 N/mm2 and 14.78 N/mm2, respectively. In terms of hardness, natural Mascarey wood presented the highest values in all three evaluated directions, with a notable value of 1013 kgf in the direction parallel to the fiber. However, in coated specimens, the highest hardness was observed in the radial direction, with values of 647 kgf for specimens coated with Monto varnish and 864 kgf for those coated with Espengloss lacquer. Furthermore, the thermal conductivity of coated Mascarey wood showed a 10 percent increase compared to uncoated specimens. In the fire reaction test, the vertical flame propagation did not exceed 150 mm in any case, classifying Mascarey wood as class D according to the EN 13501-1 standard, both in its natural state and with coatings. Although the coatings did not influence the flame propagation rate, they significantly reduced the carbonization rate. Specimens coated with Espengloss lacquer and Monto varnish recorded a carbonization rate of 0.14 and 0.19 percent, respectively. In contrast, natural specimens recorded a carbonization rate of 0.34 percent.Item Análisis de las propiedades de sección transversal de perfiles tipo UV conformados en frío(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Mecánica, 2024-08) López Espín, Jonathan David; Torrealba Toledo, Kevin Alexander; Peña Jordán, Francisco AgustínInformation on cold-formed structural elements is limited, but has become indispensable in the field of construction, as it allows for improved design and analysis of structures. In the present investigation, a comprehensive analysis of the section properties of 6 and 8 mm thicknesses was carried out. It started with a review of information to understand the behaviour of these profiles, section properties such as inertias, torsional constants and warping constants were calculated using traditional analytical methods. To validate these calculations, a mathematical model based on the finite element method (FEM) was developed, which allowed the behaviour of the cross-sections to be simulated more accurately. Experimental torsion, bending and compression tests were performed to compare the results obtained by analytical calculations and FEM analysis. In the case of the tests to determine the warping constant, technical limitations were faced, such as the lack of a high test machine for compression tests on thicker sections, which led to the use of thinner sections. Finally, the results showed that the FEM provides intermediate predictions between analytical methods and experimental tests, the differences observed in the behaviour of the specimens were discussed, conclusions were drawn on the discrepancy of results between the different methods, and recommendations for future studies were proposed, including the application of heat treatments to the profiles to improve the values obtained in the tests.Item Caracterización y fabricación de madera plástica a partir de la mezcla de aserrín de Pigüe con tereftalato de polietileno reciclado(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Mecánica, 2024-06) Mesias Erazo, Gilber Israel; Nuñez Nuñez, Omar Israel; Paredes Salinas, Juan GilbertoIn the field of Materials Engineering, the demand for improving the mechanical properties of new materials is growing. Experimental design (DOE) with response surface methodology (MSR) under Box– Behnken design was used in this experimental work. This approach allows the manipulation of three input factors with three levels each: extrusion temperature (160, 170 and 180 degrees Celsius), size of Pigüe scrape fibers (No.30, No. 40 and No. 50, under ASTM E11) and percentage of recycled polyethylene terephthalate (PET 1) (92, 95 y 98 percent). To investigate the behavior of the results obtained and identify their optimal performance points. This methodology facilitated the evaluation of mechanical properties by means of traction tests (ASTM D638-14), compression tests (ASTM D695-15) and flexion tests (ASTM D790-17), followed by the compilation and analysis of the data obtained. Traction, compression and flexion results were tabulated and an analysis was carried out which cast the following suitable case: a thimble number of 30 (ASTM E11) for the size of the particles of the shell, with a 98 percent percentage of PET 1 in the mixture and an extrusion temperature of 160 degrees Celsius. This suitable case exhibits the following mechanical characteristics: for traction, a strength of 13.97 MPa, for compression, a resistance of 3.60 MPa and for bending, a maximum effort of 19.84 MPa. Finally, the design regression model MSR reflects a global desirability value of 0.6085. Keywords: MSR, Box–Behnken, Pigue, PET recycled, DItem Influencia del tamaño nominal máximo del agregado fino en la resistencia a la compresión del hormigón simple(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2024-02) Morejón Ortiz, Anthony Xavier; Peñafiel Valla, Lourdes GabrielaConcrete, known for its wide use in construction, is distinguished by its high compressive strength. However, certain elements, such as the maximum nominal size of the fine aggregate, can vary this strength. This research addresses how variation in fine aggregate size influences the compressive strength of plain concrete. This project studies the variations in the properties of aggregates with the sizes of #4, #8, #16, #30, #50 and #100 sieves to produce concrete according to NTE INEN standards. To obtain the dosage, the optimum density method of the Central University of Ecuador was used, varying according to the size and properties of the fine aggregate. Two strengths of 240 kg/cm2 and 280 kg/cm2 were considered, then 54 cylindrical specimens of simple concrete were prepared for each strength, 9 specimens for each nominal size of the fine aggregate, which were tested at 7, 14 and 28 days. To ensure control, 3 specimens were tested at each curing time interval and accurate information was obtained to correlate the achieved compressive strength of the plain concrete with respect to the nominal size of the fine aggregate. The results reveal a progressive decrease in compressive strength as the maximum nominal size of the fine aggregate is reduced, manifesting itself noticeably in the final strength at 28 days of curing. Likewise, variations in the properties of the finer aggregate are observed.Item Influencia del tamaño nominal máximo del agregado grueso en la resistencia a la compresión del hormigón simple(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2024-02) Ruiz Gutiérrez, Nicole De Los Ángeles; Peñafiel Valla, Lourdes GabrielaThis project addresses the substantial impact that the coarse aggregate size has on the compressive strength of plain concrete. Considering sizes of 1 inch, 3/4 inch, 1/2 inch, and 3/8 inch, and design strengths of 240 kg/cm2 and 280 kg/cm2, correlations were established between both variables, considering the existing relationship between the mentioned factors. The properties of the materials to be used were determined by applying tests governed by some of the NTE INEN standards. Following this, the concrete mix designs were designed for each nominal maximum size of the coarse aggregate using the Central University of Ecuador's optimum density method. A total of 72 concrete cylinders were produced (9 for each nominal maximum size). 3 cylinders were tested according to each nominal maximum size at 7, 14, and 28 days, obtaining the necessary information for the data analysis, allowing the establishment of correlations between the nominal maximum size of the coarse aggregate and the compressive strength. The results showed a coefficient of -0.60, indicating that as the nominal maximum size of the aggregate is reduced, strengths above 100 percent of the design strength can be obtained. Similarly, when proposing correlations with the hardened density of the concrete, this coefficient was 0.74, which means that the density has a greater influence than the size. This only occurs for the sizes mentioned in this study.Item Evaluación de propiedades mecánicas de materiales compuestos fabricados a partir de envases plásticos reciclados y goma de neumáticos pulverizados(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Mecánica, 2023-09) Aleaga Ulloa, Yessenia Patricia; Valle Velasco, Pablo RaúlThis innovative technique seeks to take advantage of plastic waste and used tires, providing a sustainable and economical alternative for its reuse. The evaluation of mechanical properties is of paramount importance to determine the feasibility and performance of these composite materials. This topic focuses on the evaluation of the mechanical properties of a composite material with a resin matrix, using recycled plastic containers and pulverized tire rubber as reinforcement. Comprehensive tests and analyzes have been carried out covering compressive, flexural, tensile strength and SEM Test (Scanning Electron Microscopy). These tests allow us to measure and understand in depth the mechanical characteristics of the material, that is, its ability to support loads, resist deformation and meet specific design requirements. The use of recycled plastic packaging and pulverized tire rubber as reinforcement in the resin matrix presents a promising approach to improve the mechanical properties of the composite material. It is expected that this type of materials will contribute to the development of more sustainable and environmentally friendly products, reduce the amount of plastic waste and abandoned tires. Therefore, meticulous evaluation of the mechanical properties of these composite materials is essential to ensure their quality and applicability in various industries. The results obtained from these tests allow us to obtain crucial information for its implementation in the design and manufacture of more resistant, efficient and sustainable products in the future.Item Análisis comparativo del índice de inflamabilidad horizontal bajo la norma ISO 3795, entre materiales compuestos de matriz poliéster reforzado con fibras naturales (fibra de cabuya, fibra de chambira, fibra de coco y fibra de totora) frente a la fibra de vidrio(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Mecánica, 2023-09) Chaglla Toapanta, Bryan Joel; Castro Miniguano, Christian ByronToday, the use of composite materials is very common in various professional and industrial applications, so it is necessary to ensure that the materials meet a high level of safety for the end user. Creating composite materials lies in the sole purpose of improving their properties, therefore, in the present investigation it is intended to evaluate and compare the fire resistance of polymer matrix composite materials reinforced with natural fibers (cabuya, chambira, coconut and totora) against a synthetic fiber (fiberglass), allowing us to consider a possible substitution of synthetic materials for environmentally friendly materials, which could open a new market for their commercialization. In order to establish the appropriate percentages for the formation of composite materials, the volumetric fractions of previously carried out titling works were taken into consideration, where the percentages that provide the best characteristics of the material are detailed, having these values, the amount of resin, fiber and catalyst necessary for each configuration was calculated, after that, all these components were placed in the mold sized according to the NTE INEN ISO 3795 standard, applying manual compression on each material, once the process was completed, it was necessary to you have to wait for the curing time and verify that the new material is fully solidified. Once the samples were ready, they were sent to the LIM-UTA Mechanical Research Laboratory, to be tested, finally the combustion rate of each material was obtained, where an average of 3.61 mm/min was recorded for the Cabuya fiber, 6.72 mm/min for the Chambira fiber, 4.91 mm/min for the coconut fiber, 8.46 mm/min for the reed fiber and 9.18 mm/min for the glass fiber. Based on the results, it was possible to determine that the cabuya fiber-reinforced polyester resin composite material with a value equivalent to 3.61 mm/min is the material with the lowest propagation index compared to the other fibers evaluated.Item Análisis de las propiedades físicas y mecánicas de la madera de Seique (Cedrelinga Catenaeformis) proveniente del cantón Tena provincia de Napo y su factibilidad como elemento estructural de acuerdo con la Norma Ecuatoriana de la Construcción (NEC 2015)(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2023-09) Acosta Naranjo, José Andrés; Ureña Aguirre, Maritza ElizabethThe construction industry has a key role in global sustainability due to its high demand for resources and CO2 emissions. However, the use of materials such as bamboo and wood from sustainable forests can positively contribute to the storage of CO2 during its growth, offsetting its emssions during production. The research analyzed the physical and mechanical properties of the timber species Cedrelinga Catenaeformis from the Amazon region of Ecuador, and its suitability as a structural material according to the NEC 2015. Samples from the Tena canton were collected at 4 commercialization points, laboratory tests were carried out in accordance with the ASTM D 143-14 standard, which allowed determining the maximum stresses and the modulus of elasticity to static bending, traction and compression parallel to the fiber of each sample. When carrying out this investigation, it was possible to obtain maximum values of modulus of elasticity of tension parallel to grain of 17,603.29 MPa, compresion paralele to grain of 4,459.86 MPa, static bending of 10,723 MPa, as well as maximum admissible stresses for tension parallel to grain of 46.23 MPA, compression parallel to grain of 15.93 MPa and static bending of 30.23 MPa of Seique wood, could be compared with the requirements of the Ecuadorian Construction Standard (NEC 2015 chapter 8) determining that it is considered a timber species suitable for use as a structural element with certain limitations. . With this, it was possible to create a summary table of the physical and mechanical characteristics that would serve as a guide for the design of wooden structures in EcuadorItem Determinación de las propiedades mecánicas, compresión y flexión, para distintas relaciones de a/c en la elaboración de hormigón permeable(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2023-08) Shambi Minda, Alejandra Micaela; Navarro Peñaherrera, Carlos PatricioPervious concrete is usually used in pavements to allow water infiltration in order to reduce surface runoff and avoid interruption of the water cycle. However, this material has a high void content, so its mechanical properties tend to be lower than those of traditional concrete. In the present investigation, the resistance to compression, flexion and permeability of pervious concrete was studied, to determine the influence of the w/c ratio. For which the properties of the aggregates extracted from the “Puertas del Sol” mine were determined, later the dosage was calculated for the w/c ratios of 0.35 and 0.30 using the ACI 522R-10 method, in addition to the use of 50mm polypropylene fibers and plasticizer additive. 12 cylinders (100x200) were made for each one, permeability tests were carried out according to ACI 522R-10, in addition, the compression test was carried out at 7 and 28 days according to the ASTM C39 standard. Subsequently, beams (100x100x350) were made, with 3 test pieces for each dosage for the bending test, following the ASTM C78 standard. Once the data was tabulated, comparative graphs of the properties studied were made. This allowed us to observe that the highest compressive strength was 9.70 MPa with a permeability of 0.37 cm/s, corresponding to a w/c of 0.35. Regarding bending, the tests determined that the modulus of rupture of w/c 0.35 was 1.69 MPa, double that obtained with w/c 0.30.Item Análisis del efecto tamaño en el comportamiento a flexión y compresión de elementos de hormigón reforzado con fibras plásticas(Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2023-08) Pastuña Villegas, Bryan Alexander; Ramírez Cabrera, Wladimir JoséThe influence of the size effect on the mechanical properties of concrete is a problem studied throughout several decades of modern scientific history, however, regulations that control this deficiency have not yet been established. This project describes the flexural and compressive behavior of fiber-reinforced concrete, against this effect. For the comparative analysis, simple concrete and reinforced with macro synthetic polypropylene fibers (HRFP) were mainly designed. The dosage required to obtain a compressive strength of 240 kg/square centimeters at 28 days was quantified through the optimal density method and in the case of concrete reinforced with polypropylene fibers, a proportion of 3kg/cubic meter and 6 kg/cubic meter was added to the mix. Prismatic specimens with sizes of 100x100x350 mm, 100x200x650mm and 100x300x950mm and cylindrical specimens of 100x200mm and 150x300mm were made. The prismatic specimens were tested for bending with 4 support points according to the indications established in the ASTM C1609 standard. The cylinders were evaluated following the NTE INEN 1573 standard. The flexural results show that both the maximum resistance reached in the proportionality limit and the residual resistances that depend on the effective fibers decrease as the size of the analyzed specimen increases. It is verified that the compressive strength is also affected by the size effect, observing a decrease in effort when comparing large cylinders with respect to small ones.