Ingeniería Civil y Mecánica

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    Elaboración de concreto translúcido con distintas dosificaciones de cuarzo como reemplazo del agregado grueso para el aumento de su transmitancia luminosa
    (Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2024-08) Jácome Jácome, Pamela Giovanna; Ramírez Cabrera, Wladimir José
    The opacity of concrete limits its potential in applications that require transparency, such as facades and decorative elements. In current building projects, especially in multi-family projects, the need arises for innovative solutions to solve lighting problems, since natural light is limited and is only provided by the free fronts. In Ecuador, the demand for research in this area is urgent due to the energy crisis. The research focused on making an alternative concrete using quartz as a replacement for coarse aggregate in percentages of 10, 20 and 40 percent, to analyze its properties and its influence on compressive strength and light transmittance. Quartz sand was used as a fine material to prevent common sand from dulling the immersed quartz, however, because it did not meet the specified granulometry and fineness modulus, it was mixed with mine sand only at the necessary sieves. The results showed a variation in the absorption capacity of quartz compared to common aggregates, due to its smooth surface, which also hinders adhesion, therefore, the workability of the mixture. Regarding the compression test, it was evident that the resistance decreases as the replacement of quartz as a coarse aggregate increases, although even with this behavior, the concrete continues to meet the design strength. On the other hand, the test carried out on the spectrophotometer indicated that the incorporation of quartz increases the light transmittance.
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    Caracterización térmica, mecánica y microestructural de un material compuesto de matriz poliéster reforzada con fibra natural de banano y su posible aplicación industrial
    (Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Mecánica, 2023-09) López Martínez, Erick Isaac; Valle Velasco, Pablo Raúl
    This study investigated the feasibility of using natural banana fiber as reinforcement in a polymeric material made up of polyester resin. The banana fiber was obtained from waste produced from a banana plantation in Ecuador, making it an attractive option due to its easy availability, low cost, and low environmental impact. Three different volumetric proportions were established (80 matrix - 20 fiber, 70 matrix - 30 reinforcement and 60 matrix - 40 reinforcement) to identify the compound with the best mechanical behavior. Mechanical impact, hardness and abrasion tests were carried out, following the ASTM D5628-10, ASTM D2240-15 and ASTM G0195-13a standards, respectively. In addition, microstructure analysis was performed using a Scanning Electron Microscope (SEM) and calorimetry with a Differential Scanning Calorimeter (DSC). The results highlight that the composite material with a proportion of 70 percent polyester resin and 30 percent fiber showed the best mechanical properties, with impact energy values of 0.23J, hardness of 73.1 Shore D, abrasion index of 23.4 (mg/cycle) and a peak temperature of 113.88 degrees Celsius. Banana fiber represents a promising alternative as reinforcement in polyester resin composites, and the composite with the ratio of 70 percent matrix and 30 percent reinforcement demonstrated optimal mechanical behavior. These results have important potential applications in various industries, such as construction, automotive, and aeronautics.
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    Análisis de aluminosilicatos como material de sustitución parcial del cemento tipo GU en la construcción
    (Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2021-02) Yanchaguano Toapanta, Doris Verónica; Coello Fiallos, Diana Carolina
    In this work, the study of physical, chemical, and mechanical properties was carried out, mainly encompassing density and fineness, applying the INEN 0156 and INEN 0489 standards respectively with Natural Zeolite samples: ZR, ZC collected from rock of the Mina Zeonatec and ZCa obtained from the Calmosacorp S.A. processor, as well as from the CGU cement. The results obtained from the tests carried out with respect to density show values of 2.304, 2.330, 2.339 and 3.075 grams per cubic centimeter, in the same way the results of finesse 99.83, 99.71, 99.87 and 99.95 percent with zeolites ZR, ZCa, ZC, and CGU respectively are presented. With chemical characterization morphology was obtained by SEM, where in the analysis they showed similarity between samples, especially when analyzing SEM images of the CGU and ZC samples, where the shape of the crystals are angular polyhedral with superficially fine sizes and mostly flat grains. The EDS analysis is also known for the concentration of chemical elements that make up each of the samples studied and the silicon-aluminum ratio contained in such samples, thus outstanding the Si/Al ratio of ZCa with a value of 4.52 dimensionless which represents better concentration than the same CGU with 3.4. Zeolites with better properties were compared, concluding that zeolite ZC presents conditions suitable for replacement by CGU since both density, fineness and morphological characterization showed results close to cement.
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    Estudio de las propiedades físicas de zeolita natural (aluminosilicato) de tipo clinoptilolita para remplazo parcial del cemento portland
    (Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2021-01) Salcedo Rivera, Verónica Elizabeth; Coello Fiallos, Diana Carolina
    This study shows physical and chemical characteristics of natural zeolites (ZN) called ZA, ZZ, ZI from outcrops of the Chongón Colonche Mountain range located in the Guayas province of Ecuador and of the cement Type GU (CGU) for commercial use, with the purpose to determine if they can be supplemental cement material (SCM). Physical characteristics (density and fineness applying INEN and ASTM standards), morphological characteristics in the Scanning Electron Microscope (SEM) and elemental composition are determined by X-ray scattering spectroscopy (EDS). Prior to the tests, the samples that require grinding are prepared to obtain granules smaller than 75 microns. Densities of 3,071, 2,449, 2,511 and 2,494 grams per cubic centimeter and fineness percentages of 99.95, 99.04, 99.51, and 99.35 are obtained for CGU, ZA, ZZ and ZI, respectively. The experimental results, SEM micrographs and EDS spectra reveal that all samples have potential as SCM, highlighting ZA and ZZ with characteristics closer to CGU. All have a high pozzolanic capacity in the content of silica, alumina and iron oxide, exceeding the minimum specified by the ASTM C 618 standard. On the other hand, the siliconaluminum ratio between 2.67 and 4.83 shows the presence of clinoptilolites that have demonstrated efficacy as SCM. The compatibility in terms of its structure, sizes and chemical composition is obvious, however, for subsequent studies it should be taken into account that CGU cement is highly silicic compared to other cements used in studies with zeolites.
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    Estudio comparativo de las propiedades físicas de aluminosilicatos del cantón Guayaquil para sustitución parcial del cemento portland IP
    (Universidad Técnica de Ambato. Facultad de Ingeniería Civil y Mecánica, Carrera de Ingeniería Civil, 2021-01) Fernández Álvarez, Ramiro Paul; Ureña Aguirre, Maritza Elizabeth
    Since cement is a natural or artificial material present in almost all the buildings in the world, it is normal to say that it is the consumer of large amounts of natural resources and emitter of carbon dioxide, so there is a need to find a substitute of cement for sustainable and environmentally friendly materials. In the Civil Engineering laboratories, the physical (morphology, density, grain size, fineness) and chemical properties of the aluminosilicates ZA, ZI, ZZ (zeolites) of the canton of Guayaquil were compared with those of Selva Alegre IP cement. Apply the density test using the NTE INEN-156 standard, obtaining values of ZZ equal to 2,514, ZI equal to 2,485, and ZA equal to 2,445 grams on cubic centimeter by pycnometer calibration and other values of ZZ equal to 2,353, ZI equal at 2,233, and ZA equal to 2,408 grams per cubic centimeter at room temperature, which indicate that the density of the zeolite is very variable. I present the final percentages of fineness according to NTE INEN-489 of the samples of ZZ equal to 99.51, ZA equal to 99.04, ZI equal to 99.35, which are optimal in constructions and are compared with the percentage of IP cement equal to 99.72, grinding and granulometric graphs are also presented as an additional contribution to the investigation. On the other hand, the morphological and chemical characterization is indicated, by microscopy, the EDS showed a homogeneous distribution of elements of the zeolites with respect to the cement, but a heterogeneous quantity in percentages of each element. Defined cubic crystalline structures and other amorphous forms with dimensions from 1 to 20 microns were observed in the SEM of IP cement, differing from ZZ, ZI, ZA that presented crystals with irregular surfaces and undefined, elongated and polyhedral structures with dimensions ranging from 1 to 50 microns. The final results of the physical and chemical tests show the feasibility of using these aluminosilicates as a material with potential cementing characteristics to be a substitute for Selva Alegre IP Portland cement.