Browsing by Autor "Jahel Sarvia Ledezma Perez"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    Item type: Item ,
    Análisis de la variabilidad horaria para la detección de daños en pavimentos flexibles usando termografía infrarroja
    (2020) Marina Pacara Copa; Joaquín Humberto Aquino Rocha; Jahel Sarvia Ledezma Perez
    En este trabajo se discute el rango horario para optimizar e interpretar los resultados de la termografía infrarroja cuando es utilizada en la detección de daños de pavimentos flexibles. Se realizó un seguimiento de 14 horas continuas (5:00 a.m. a 7:00 p.m.) para cuatro zonas de estudio en una avenida céntrica de la ciudad de Cochabamba, Bolivia. El seguimiento evidenció un rango horario óptimo para la toma de imágenes termográficas de 11:00 a.m. hasta las 4:00 p.m.; también se constató la visualización del deterioro mediante la colorimetría diferenciada en los termogramas a diferentes horas. Este ensayo permite localizar las áreas en las que se puede efectuar una inspección detallada. Como limitante se tiene su sensibilidad a cambios en las condiciones ambientales.
  • Thumbnail Image
    Item type: Item ,
    Use of recycled plastic bottle caps (RPBC) as partial sand replacement in cement mortars: Mechanical and CO₂ emissions assessment
    (Elsevier BV, 2025) Joaquín Humberto Aquino Rocha; Ricardo César Solís; José Luis Martínez; Joel Gerson Peredo Villarroel; Victor Hugo Miranda Challapa; Jahel Sarvia Ledezma Perez; Nahúm Gamalier Cayo Chileno; Romildo Dias Toledo Filho
    This study evaluates the use of recycled plastic bottle caps (RPBC), composed of high-density polyethylene (HDPE), as a partial replacement for natural sand in cement mortars. Mixes with varying RPBC contents (0 %, 10 %, 25 %, 50 %, 75 %, and 100 %) were developed to analyze their mechanical, microstructural, and environmental behavior. Tests included compressive strength, splitting tensile strength, and ultrasonic pulse velocity (UPV) at 7, 28, and 56 days, along with scanning electron microscopy (SEM) analysis. Additionally, CO₂ emissions associated with each mix were estimated, considering the material content and energy consumption during RPBC crushing, under two emission scenarios for sand. Results showed that incorporating up to 25 % RPBC does not significantly affect the mechanical properties of the mortar. However, a considerable decrease in mechanical performance was observed at replacement levels above 50 %, attributed to the low adhesion between recycled HDPE and the cementitious matrix, as well as its hydrophobic nature, which leads to increased porosity and a higher effective water-to-cement ratio. From an environmental standpoint, a progressive reduction in CO₂ emissions was observed with increasing RPBC content. Nevertheless, the eco-efficiency indicator (kg CO₂/(m³·MPa)) revealed that structural/environmental efficiency decreases for replacements above 50 %. The use of RPBC is technically and environmentally viable up to 25 %, offering a sustainable option for revalorizing plastic waste in construction.