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- ItemAnalysis of seismic coupling in rupture zones of the andean subduction margin and its relationship with the seismo-tectonic context(2025) Becerra Carreño, Valeria Camila; Crempien de la Carrera, Jorge; Yáñez Carrizo, Gonzalo Alejandro; Pontificia Universidad Católica de Chile. Escuela de IngenieríaIn Chile, a highly seismic country, it is essential to understand the processes that generate earthquakes due to their impact to society. To achieve this, co-seismic slip and interseismic coupling models are commonly analyzed using instrumental observations such as seismometers and GPS receivers. Due to the distance and distribution between the seismic source and the data, inversion methods are used to estimate models consistent with fault mechanics. The seismic potential of the region is assessed using multiple simultaneous approaches such as the coupling analysis on the main fault. This work proposes to integrate seismic cycle knowledge and geodetic data into an advanced inversion methodology to improve seismic coupling estimation and better characterize earthquake hazards in regions of interest. We use an approach based on the analysis of both slip deficit and accumulated energy at the plate interface, which are directly related to the physics of rupture processes. A Bayesian inversion method is developed which incorporates spatial correlations of kinematic (backslip) and mechanical coupling models (stress rates) and the quantification of uncertainties. Both methods are validated with synthetic tests and applied to two regions of Chile: the central zone, characterized by the 2010 Mw 8.8 Maule and 2015 Mw 8.4 Illapel earthquakes, and the north-central zone, a high-potential seismic gap. The models obtained show strong correlations with seismic and gravity anomaly observations, allowing a better understanding of the relationship between subduction processes and earthquake generation. These results are essential to understand potential seismictectonic segmentation and for estimating the seismic and tsunamigenic risk in the Andean region.
- ItemNumerical modeling of Mass transport in Turbulent environmental flows(2025) Barros Alcalde, María Magdalena; Escauriaza Mesa, Cristian Rodrigo; Pontificia Universidad Católica de Chile. Escuela de IngenieríaMass transport in turbulent environmental flows is strongly influenced by the unsteady dynamics of coherent structures. The accurate prediction of mass transport in these turbulent systems is essential for effective management of water resources, the preservation of ecosystems, and long-term environmental sustainability. In nature, environmental flows are typically non-uniform and characterized by complex turbulent phenomena such as Flow separation, recirculation zones, and shear layers. In many of these flows, the fundamental mechanisms governing turbulent mixing and transport remain poorly understood. To advance our understanding of these transport mechanisms, large-eddy simulations (LES) were performed coupled with scalar and particle transport models to capture the interaction between coherent structures and mass transport processes. These simulations use high spatial and temporal resolution to directly resolve the relevant scales for transport. Two complex flows were investigated: (1) The Eulerian and Lagrangian transport of apassive scalar in the flow past a lateral cavity, and (2) bedload transport through an array of boulders over a rough bed. In the first investigation, the results showed that columnar vortices and longitudinal structures periodically shed and advected along the shear layer govern mass transport and the exchange across the cavity interface. Additionally, the isolated low-speed vortex inside the cavity plays a significant role, as its core retains mass for long periods. This study elucidates the role of coherent structures in driving mass transport by linking their dynamics to the spatial distribution of Lagrangian residence times, particle trajectories, and finite-time Lyapunov exponents (FTLE). Furthermore, an upscaling of these small-scale processes was achieved by incorporating a fractional derivative into the evolution equation for the concentration inside the cavity, effectively capturing the large-scale memory effects observed in the simulations. These findings constitute a novel contribution that offers important insights into the underlying mechanisms of mass transport and provide a valuable framework to improve predictions of the transport and dispersion of contaminants.In the second investigation, the simulations revealed complex vorticity patterns resulting from the interaction between the boulder wakes and the rough bed, as well as the presence of arch vortices, longitudinal structures and three-dimensional shear layer vórtices downstream of the boulders. These features were found to significantly influence near-bed turbulence, bedload transport rates, and sediment deposits. Notably, the effect of the observed coherent patterns in bedload fluxes persisted after averaging at larger scales, highlighting the importance of the flow spatial variability induced by the macroroughness elements. This investigation provides valuable insight into bedload transport processes at the grain scale, offering a clearer understanding of the exact flow perceived by the sediments. The energy and momentum mechanisms were further examined using the double averaging methodology (DAM), which allowed the upscaling of the turbulence generated at the roughness level to a larger-scale framework. This analysis clarified the mechanisms through which stresses and energy are generated and redistributed in the flow. A key finding for bedload transport is that the total fluid stress acting on the bed was found to be approximately half of the value estimated using the classical depth-slope product. This result supports previous observations that conventional methods tend to overpredict bedload transport in flows with macroroughness elements.
- ItemIntegration of electrochemical decarbonation of limestones into an innovative chain for low carbon foot print cement production(2025) Ramírez Amaya, Darío Alonso; González Hormazabal, Marcelo Andres; Pontificia Universidad Católica de Chile. Escuela de IngenieríaConcrete is the most widely used human-made material, but its use faces pressing challenges related to reducing CO2 emissions. These emissions are primarily associated with the cement production processes, which involve the calcination of calcium carbonate (CaCO3)-rich limeston esto produce quicklime (CaO), hydrated lime (Ca(OH)2), and clinker —the main active compound in Portland cement (PC). Due to the growing demand for concrete and, consequently, cement, the cement industry increasingly relies on disruptive technologies to meet CO2 stabilization targets for2050, which are essential for contributing to less severe global warming scenarios. Recently, an electrochemical process based on water electrolysis has been proposed as a disruptive technology with potential for the deep decarbonization of lime and cement production. In this process, introducing solid CaCO3 into an electrolysis cell triggers a decarbonation reaction in anaqueous medium at room temperature and atmospheric pressure, releasing H2, and a mixture of O2 and CO2. Calcium precipitates as solid Ca(OH)2 and is recovered from the electrolysis cell by filtration. This precipitated material (PM) has the potential to be used as a non-carbonate feedstock for lime and cement production (Ca(OH)2 Heat→ CaO + H2O), addressing the chemical emissions produced by limestone calcination (CaCO3 Heat→ CaO + CO2). For a future deployment of this technology in the cement industry, it is essential to understand the implications of electrochemical decarbonation (ED) in the manufacturing process and the final product's performance. Accordingly, this research focused on the integration of the ED into an innovative chain for low-carbon footprint cement production, advancing the understanding of the fundamentals of the electrochemical process, and investigating the effects of substituting natural limestone with its corresponding PM on the entire production chain and the properties of the resulting cement. The physical and chemical properties of limestones from cement plants were of interest in explaining the quality of the PM. For this purpose, different-grade limestones were decarbonated using an H-type cell, demonstrating that ED is possible on natural limestones of different CaCO3 purities. In all cases, the PM obtained was mainly comprised of Ca(OH)2, with a higher CaO concentration and lower loss on ignition (LOI) than their precursors, which is beneficial for cement and lime production. The quality of the PM as a feedstock for cement and lime production was assessed according to the state of practice in these industries. It was demonstrated that regardless of the CaCO3 purity and origin of the precursor limestone, the ED enhances the lime saturation factor due to an increase in the CaO concentration while reducing the rest of primary oxides and impurities of the precursor, which can be separated from the calcium component and isolated in the cell's anodic chamber by decantation. For most of the studied cases, PMs' chemical and physical characteristics supported the ED suitability for cement and hydrated lime production. In this sense, low fineness and specific surface area of the precursor, along with a high content of MgO, were linked to an increase in unreacted CaCO3 in the PM. The effect of using PMs on the cement manufacturing process was initially evaluated by identifying and quantifying the main hydraulic phases and free lime content in laboratory synthesized electrochemical clinker (E-CK). It was demonstrated that the raw meal for E-CK can be formulated by completely replacing the precursor limestone with its PM, reducing CO2 chemical emissions up to 90%. After the clinkerization stage, the resulting E-CK was mainly comprised of Alite (C3S), and the rest of the hydraulic phases remained in suitable proportions for Portland cement production. In addition, under the same thermal treatment, the raw meal formulations based on PM had a lower free lime content than conventional formulations based on the precursor limestones. It was suggested that the high reactivity of the alternative raw meal is due to the lower enthalpy and temperature of decomposition of the Ca(OH)2 dehydroxylation compared to CaCO3 decarbonation.
- ItemImpact on patient waiting and service downtime due to nonstructural earthquake damage of Hospital critical rooms(2025) Guamán Cabrera, Jaime Wilson; Llera Martin, Juan Carlos de la; Pontificia Universidad Católica de Chile. Escuela de IngenieríaProveer cuidado médico continuo y estabilizar a pacientes gravemente heridos son servicios críticos que los hospitales ofrecen durante emergencias causadas por terremotos. Sin embargo, durante las últimas décadas muchos hospitales alrededor del mundo han sufrido daño no estructural significativo que ha impactado severamente la funcionalidad de los servicios médicos, reduciendo drásticamente su capacidad de respuesta hospitalaria. Actualmente, existe escasa investigación acerca de cómo correlacionar adecuadamente el daño de elementos no estructurales, sistemas, y contenidos (NSC) con la funcionalidad de recintos críticos hospitalarios y su posterior recuperación. Para abordar este vacío de conocimiento, esta investigación se enfoca en la estimación del impacto del daño de NSC en la Funcionalidad Residual (RF) y Tiempos de Espera de pacientes (WT) en recintos críticos hospitalarios. Para lograr esto, en primer lugar, la Técnica de Proyección de Cámara (CPT) fue usada para extraer las respuestas experimentales del equipamiento médico instalado en el edificio de cinco pisos, ensayado a escala natural en la Universidad de California San Diego, en 2012. Segundo, tres modelos numéricos no lineales, es decir, rodante, deslizante, y balanceo-vuelco, fueron desarrollados en MATLAB para reproducir las respuestas experimentales obtenidas en CPT. Luego, dos modelos de edificios hospitalarios tridimensionales y completamente equipados fueron desarrollados en OpenSees para simular un Box de Urgencia (ER), una Unidad de Cuidados Intensivos (ICU), y un Recinto Operatorio (OR) en el primer, cuarto, y quinto piso, respectivamente, considerando ambos sistemas de apoyo, Fijo-a-la-Base (FB) y Base-Aislada (BI). Ambos modelos hospitalarios fueron analizados para estimar su desempeño y daño estructural, no estructural, y de contenidos de forma progresiva para los sismos de Servicio (SE), Diseño (DE), y Máximo Sismo Considerado (MCE), y para ambos sistemas de apoyo. Luego, curvas de fragilidad estructural y de contenido médico no anclado fueron específicamente desarrolladas en este estudio usando Análisis Dinámico Incremental (IDA). Posteriormente, se adoptó una metodología probabilística para construir escenarios de daño no estructural usando modelos 3D de Realidad Virtual (3D-VR) mediante el acoplamiento de curvas de fragilidad estructural y no estructural usando 10,000 Simulaciones Monte Carlo (MCS). Luego, estos escenarios 3D-VR fueron usados para llevar a cabo elicitaciones a expertos médicos con la finalidad de obtener opiniones imparciales para RF y WT para cada recinto crítico, nivel de demanda sísmica, y condición de apoyo. Finalmente, los juicios de expertos fueron procesados usando el método Cooke para construir curvas de fragilidad discretas para RF y WT. Esta investigación busca contribuir a un mejor entendimiento del daño NSC, su interacción con el desempeño estructural, y su impacto en la continuidad de servicios médicos.
- ItemRecovery of Murta polyphenols using eutectic solvents and advanced sustainable techniques(2025) Fuentes Jorquera, Natalia Andrea; Pérez C., José Ricardo; Canales Muñoz, Roberto; Pontificia Universidad Católica de Chile. Escuela de IngenieríaUgni candollei B. (murta blanca) y Ugni molinae T. (murta roja), son especies nativas silvestres chilenas que tradicionalmente han sido utilizadas en medicina etnobotánica, poseen perfiles polifenólicos diversos y poco explorados, especialmente en el caso de la murta blanca. Técnicas analíticas avanzadas, como UPLC-ESI-ORBITRAP MS y UHPLCESI-QTOF, han identificado una amplia gama de compuestos fenólicos en frutos, hojas y tallos, incluyendo numerosas estructuras nuevas. Las bayas de murta blanca revelaron más de 100 compuestos fenólicos en sus extractos, mientras que los extractos de murta roja demostraron un potencial antioxidante significativo, especialmente en las hojas. Los métodos sostenibles de extracción influyeron significativamente en el rendimiento y la composición de polifenoles. Es así, como técnicas avanzadas tales como la extracción asistida por microondas (MAE) y la extracción asistida por ultrasonido (UAE), combinadas con solventes eutécticos (ES), mejoraron el rendimiento de la extracción cuando se optimizaron. Específicamente, para las condiciones del ES, ChCl:1,3-butanodiol con 30% de agua y MAE a 353 K durante 3 min produjo el mayor contenido de polifenoles extraíbles (EPP). Por otro lado, los polifenoles no extraíbles (NEPP), principalmente proantocianidinas, contribuyeron hasta el 19% del total de polifenoles, lo que resalta su importancia. La extracción con líquidos presurizados (PLE) con glicerol acuoso mejoró la recuperación de compuestos fenólicos de hojas y tallos, mientras que la maceración convencional favoreció algunos compuestos del fruto. Estos hallazgos respaldan el uso de métodos de extracción ecológicos para obtener compuestos antioxidantes de alto valor a partir de murta, promoviendo su aplicación en las industrias alimentaria y nutracéutica. Este estudio está alineado con los principios de la economía circular, la revalorización de residuos agroalimentarios y los Objetivos de Desarrollo Sostenible (ODS) de las Naciones Unidas.