Doctoral School

Reading date: 23/10/2026

• BAJIC, PETAR: Assessment of structural performance of fibre-reinforced concrete under chloride-induced corrosion
  
  Author: BAJIC, PETAR
  Programme: DOCTORAL DEGREE IN CONSTRUCTION ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 17/09/2026
  Reading date: 23/10/2026
  Reading time: 11:00
  Reading place: CAMPUS NORD - Carrer de Jordi Girona, Les Corts, 08034 Barcelona - Edifici B1-003
  Thesis director: DE LA FUENTE ANTEQUERA, ALBERTO | TOSIC, NIKOLA
  Thesis abstract: Chloride-induced corrosion is a major contributor to the degradation of steel-based products (i.e., bars, fibres, and others) used to reinforcing concrete structures. Namely, chlorides, if present in sufficient concentration, degrade the protective oxide layer that forms around the steel-based products in an alkaline environment, such as that existing in concrete. In the ensuing electrochemical reaction, the steel cross-section is reduced and consequently structural performance (in terms of load-bearing capacity and ductility) is degraded. It is well established that cracking, which normally occurs during service in reinforced concrete elements under bending, detrimentally affects durability and, by extension, overall structural performance. Conversely, the addition of fibres to a concrete matrix is widely recognized to enhance post-cracking performance by effectively arresting macro-crack growth. Consequently, investigating the extent to which fibre reinforcement can mitigate durability degradation constitutes a vital advancement in structural engineering research.With the goal of assessing the structural performance of different concrete types (with and without using fibres in combination with traditional rebar), in this study, a comprehensive experimental program was performed. In the experimental matrix three different concrete types were considered: conventional (rebar-only) reinforced concrete (RC) and two variants of rebar-reinforced fibre-reinforced concrete (RR-FRC). Specifically, rebar-reinforced steel-fibre-reinforced concrete (RR-SFRC) and rebar-reinforced polypropylene-fibre-reinforced concrete (RR-PPFRC). The test matrix consisted of: three distinct loading conditions (non-loaded, unloaded and elements under sustained flexural loads), two cracking states (cracked and non-cracked elements) and two exposure conditions (elements exposed to a 3% sodium chloride solution and non-exposed elements). The research was conducted both on small-scale elements (in laboratory conditions) and large-scale elements (in-situ conditions) The results indicate comparable corrosion kinetics across all considered concrete types, characterized by similar periods of corrosion initiation and propagation. However, despite fibres functioning as an invariant parameter relative to corrosion kinetics, the RR-FRC elements exhibited superior structural performance relative to the traditional RC elements. In certain instances, the mechanical performance of corroded RR-FRC elements surpassed that of the non-corroded RC controls. Moreover, the RR-FRC elements demonstrated superior behaviour under long-term sustained loading; they exhibited the capacity to recover a significant portion of their deformation upon unloading, whereas the conventional RC elements sustained permanent, irreversible deformation.
  

• MURILLO GOMEZ, NELSON ENRIQUE: COASTAL HAZARDS, RISKS AND ADAPTATION IN THE BARRA DE SALAMANCA (COLOMBIA)
  
  Author: MURILLO GOMEZ, NELSON ENRIQUE
  Programme: DOCTORAL DEGREE IN MARINE SCIENCES
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 16/07/2026
  Reading date: 23/10/2026
  Reading time: 11:00
  Reading place: Place: ETSECCPBUPC, Campus NordBuilding C2. Classroom: 212C/Jordi Girona, 1-308034 Barcelona
  Thesis director: JIMENEZ QUINTANA, JOSE ANTONIO
  Thesis abstract: Coastal sandbars are generally elongated landforms that provide protection to environmental, socioeconomic, and infrastructural ecosystems from extreme events, but are highly sensitive to morphodynamic changes driven by natural and anthropogenic processes. This is further complicated by the uncertainty Surrounding the expected sea-level rise in the coming years. These dynamics generate pressures and motivate land managers to understand the genesis of their morphological evolution, the physical agents that modulate it, the risks associated with the diversity of their exposed ecosystems within a tolerance limit, and to propose sustainable adaptation measures for the future.This research reconstructs the morphological evolution of the Salamanca coastal sandbar (Colombia), located within a national and international conservation park, over the last 40 years, the physical agents present at decadal and episodic scales, and the assessment of threats associated with erosion and flooding. Understanding the past and considering sea level rise projections to 2050, a projected area susceptible to damage was identified. Within this area, the exposure and vulnerability of the exposed elements were assessed, and this, when integrated with the threats, allowed for the estimation of environmental, physical, and socioeconomic risks. Recognizing that risk cannot be eliminated because it is intrinsic to coastal development, we have proposed a model of tolerable risk levels and a list of adaptation measures grouped into strategies according to their implications for the coastal zone. The results showed that the sandbar is decreasing its sediment transport rates, indicating a search for morphological equilibrium. However, erosion rates of around -20 m/a at the most critical points are deteriorating environmental services. This, combined with storm impacts and the increasing construction of hard infrastructure, has worsened and increased the exposure of the main land-based infrastructure connecting the region's most important towns with the interior of the country. This is putting commercial and tourism activities at risk. The communities located in these areas are in highly vulnerable socioeconomic conditions, generating pressure on the coastline that requires urgent intervention. The tolerable risk for environmental, physical infrastructure, and socioeconomic factors was established according to the degree of impact on the exposed element, its loss of natural value, and the resulting repercussions on the quality of life of the inhabitants. This criterion facilitates a balance of sustainable development between the inhabitants and their environment. The risk reduction strategies demonstrated that acting alone does not achieve tolerable risks, and only a comprehensive strategy allows us to approach the proposed objectives. Prompt action is needed to reduce uncertainty and increase objectivity about the expected future. We conclude that the methodology developed allowed us to understand what has happened, why, under what conditions the threats have evolved, the morphological evolution, the risk typologies, what could happen, and how to reduce the probability of the expected changes. We believe this methodological process can be replicated and adapted to any coastal area with the specific characteristics required. keywords: morphology, risks, adaptation measures.
  

Reading date: 26/10/2026

• GOUMEIDA, KENZA: Consumer and Citizen Preferences Towards Sustainability Attributes and Practices
  
  Author: GOUMEIDA, KENZA
  Programme: DOCTORAL DEGREE IN SUSTAINABILITY
  Department: University Research Institute for Sustainability Science and Technology (IS.UPC)
  Mode: Normal
  Deposit date: 28/09/2026
  Reading date: pending
  Reading time: pending
  Reading place: pending
  Thesis director: GIL ROIG, JOSE MARIA | RAHMANI MEDDOUR, DJAMEL
  Thesis abstract: The transition towards sustainable food systems is widely recognized as one of the major challenges of our time, spanning the production, processing, marketing, and consumption of food. While research on the social, environmental, and economic dimensions of this shift is extensive on the supply side, less is known about the demand side: how consumers and citizens value and act upon sustainability attributes embedded in food products and dietary practices. This thesis addresses this gap by examining consumer and citizen preferences towards sustainability attributes and practices at three points of the food value chain: production, product/distribution, and consumption. Three specific objectives follow: i) to estimate citizens' willingness to support the environmental, social, and economic benefits of more sustainable pig production; ii) to examine consumers' valuation of sustainable, biodegradable food packaging and how it changes as information grows, identifying the underlying consumer segments; and iii) to identify the latent drivers and segments of adherence to a healthy, sustainability-relevant dietary pattern across Spain, Morocco, and Turkey, together with their explanatory factors.For the production objective, a discrete choice experiment (DCE) was administered via an online survey and analyzed with a conditional logit model (CLM) to estimate willingness to pay (WTP) for ecosystem service attributes. Results show significant citizen support for a shift towards lower crude-protein pig diets that reduce environmental emissions and soybean use while improving animal welfare. Support is highest for the greatest environmental improvement and differs across sociodemographic groups, particularly by gender and rural/peri-urban residence, indicating that support for upstream production changes is real but conditional rather than universal.For the product/distribution objective, a non-hypothetical, incentive-compatible experimental auction (EA) was conducted face-to-face using a sequential information disclosure design combined with a hybrid latent class model (HLCM). Results show that consumers' WTP for sustainable packaging builds cumulatively as information progresses from an abstract environmental claim, to physical interaction to full market presentation, indicating that environmental and sensory information reinforce rather than compete with each other. Two consumer segments emerge, "Low-engagement bidders" and "Premium green adopters", differing in their adoption of the sustainable option and in how strongly information shifts their valuation.For the consumption objective, a cross-sectional online survey conducted independently in Spain, Turkey, and Morocco was analyzed using country-specific hybrid latent class models and pooled direct-effects regressions to test formally for cross-country differences in adherence to the Mediterranean diet (AMD). Two comparable segments, "High adherents" and "Moderate adherents", are identified in each country, with nutrition knowledge as the only determinant common to all three. The remaining psychosocial, household, and sociodemographic drivers differ meaningfully across countries, showing that sustainable dietary behavior cannot be explained by a single, universal set of factors.Overall, the three chapters show that sustainability is valued conditionally rather than uniformly along the food value chain. Its value depends on the scale of the benefit at stake, on how sustainability information is communicated, and on who the individual is. Combining these three perspectives within one coherent value-chain narrative provides conceptual, methodological and empirical insight into how demand-side responses to sustainability actually operate throughout the food system, with practical implications for producers, retailers, consumers, and policymakers designing more effective, better-targeted sustainability interventions.
  

• LEYVA SANTES, NEIEL ISRAEL: High Performance Network-on-Chip Designs for Open Manycore Systems
  
  Author: LEYVA SANTES, NEIEL ISRAEL
  Programme: DOCTORAL DEGREE IN COMPUTER ARCHITECTURE
  Department: Department of Computer Architecture (DAC)
  Mode: Normal
  Deposit date: 16/09/2026
  Reading date: 26/10/2026
  Reading time: 11:00
  Reading place: Sala C6-E106
  Thesis director: ÁLVAREZ MARTÍ, LLUC | VALLEJO GUTIÉRREZ, ENRIQUE
  Thesis abstract: The transition from multicore to manycore architectures is a direct consequence of the limitations of frequency scaling and the need to sustain performance growth through parallelism. As a result, modern processors integrate an increasing number of cores within a single chip, which significantly raises the demands on on-chip communication and memory systems.In parallel, open instruction set architectures such as RISC-V have enabled the emergence of open hardware ecosystems, where full-system platforms can be designed and explored at the Register-Transfer Level (RTL). Over time, open manycore platforms have evolved from simple educational designs into more complete and scalable infrastructures, incorporating coherent memory hierarchies and Network-on-Chip (NoC) interconnects. This evolution has positioned them as promising candidates not only for reproducible architectural research, but also as realistic foundations for the design and evaluation of future high-performance computing systems. However, reaching this level of applicability requires further improvements in scalability and efficiency, particularly in communication and memory subsystems.In this context, this thesis focuses on advancing the maturity of an open manycore platform to support both architectural research and the development of high-performance computing systems. The objective is to provide a flexible and scalable infrastructure that enables detailed evaluation at the RTL while remaining representative of realistic HPC workloads and supporting system design. To achieve this, the thesis focuses on improving the communication and memory subsystems, as they play a key role in determining system scalability and overall performance. The proposed approach combines methodological and architectural contributions to reduce evaluation cost, enhance system performance, and extend platform configurability. The thesis is structured around three main contributions.First, it presents SynFull-RTL, a methodology for evaluating RTL NoC designs using traffic models derived from real application behavior. By leveraging probability-weighted sampling of execution macro-phases, this approach significantly reduces simulation time while preserving representativeness, achieving up to 40x reduction in time-to-solution.Second, the thesis introduces OpenPiton4HPC, a set of architectural extensions that improve memory bandwidth, reduce communication latency, and increase system configurability. These enhancements include support for multiple memory controllers, NoC optimizations such as router bypassing and wider links, and a tunable cache hierarchy, leading to performance improvements of up to 7.2x over the baseline.Finally, the thesis proposes GS-NoC, a hardware mechanism designed to improve communication efficiency for irregular memory access patterns in vector workloads. By coalescing memory requests at different levels of the system, GS-NoC reduces the number of NoC packets by 52% on average with respect to the Bypass configuration and achieves a geometric mean speed-up of 1.18x compared to a baseline NoC configuration.All contributions are implemented at synthesizable RTL and validated through cycle-accurate simulation, ensuring realistic evaluation and practical applicability. Overall, this work advances the design of open manycore platforms, improving their scalability and effectiveness as research and development infrastructures for future computing systems.
  

• MINI DAS, APARNA: Investigation of Dynamic Catalyst -Electrolyte Interfaces in Electrochemical Systems for Establishing Activity Correlations.
  
  Author: MINI DAS, APARNA
  Programme: DOCTORAL DEGREE IN PHOTONICS
  Department: Institute of Photonic Sciences (ICFO)
  Mode: Normal
  Deposit date: 28/09/2026
  Reading date: pending
  Reading time: pending
  Reading place: pending
  Thesis director: GARCÍA DE ARQUER, FRANCISCO PELAYO
  Thesis abstract: Rising atmospheric CO2 levels, driven primarily by anthropogenic emissions, are a central contributor to global climate change and environmental instability. Electrocatalytic reactions provide a promising pathway for CO2 emission reduction through electricity-driven conversion of CO2 and/or water into value-added chemicals and fuels. In this context, catalysts are widely recognized as the key determinants of performance. This thesis takes the discussion a step further by examining how, in specific reactions, not only the catalyst itself but also the surrounding environment becomes crucial in defining performance matrices. More specifically, it investigates dynamic catalyst-electrolyte interfaces in water electrolysis and direct bicarbonate reduction, with a particular emphasis on interfacial dynamics and their correlation with activity.The thesis first outlines the fundamental aspects of water electrolysis and bicarbonate reduction, and then presents new concepts and findings on the role of dynamic catalyst-electrolyte interfaces in these systems. To do so, several in situ and operando techniques are employed, including Raman spectroscopy, X-ray absorption spectroscopy, electrochemical impedance spectroscopy, and quantitative bubble analysis, complemented by other electrochemical methods to establish correlations with performance.In the case of water electrolysis, the thesis focus on the oxygen evolution reaction, which represents the largest energetic penalty in the system. Correlations spanning atomic to microscale features are identified, collectively shaping the performance landscape of the reaction. Using complementary in situ probes, these correlations are shown to go beyond simple cause-and-effect relationships, highlighting the importance of uncovering the underlying mechanisms rather than relying solely on performance metrics.In direct bicarbonate reduction, performance is strongly influenced by the availability of CO2 at the interface, which is in turn linked to the local pH. Through operando Raman spectroscopy, a descriptor for the interfacial buffering state is identified, providing indirect insight into instantaneous CO2 availability. This hypothesis is further validated by engineering the catalyst-electrolyte interface to actively tune this descriptor, resulting in a threefold improvement in performance. This demonstrates how mechanistic understanding of the catalyst-electrolyte interface can guide informed hypotheses that are ultimately deterministic, reducing the experimental parameter space and improving optimization efficiency.Overall, the thesis emphasizes the importance of understanding why performance improves, rather than simply attributing progress to “better catalysts”. A deeper understanding of these systems, especially at high current densities, can lead to more coherent design principles and challenge existing assumptions about major factors governing the electrochemical performance. The results show that the catalyst surface cannot be considered a static entity, but rather a dynamic system whose structure and reactivity are continuously modulated by external factors. These insights provide a more detailed mechanistic picture of electrochemical interfaces and help identify key descriptors for catalyst design.