https://hdl.handle.net/2072/453063 2026-04-04T16:15:55Z https://hdl.handle.net/10256/28406 Finite element modelling of cracking behaviour of reinforced concrete tensile members using a phase field approach Barahona, Mario D.; Carreras Blasco, Laura; Barris Peña, Cristina Modelling the cracking behaviour of reinforced concrete (RC) elements remains a major challenge due to the inherent heterogeneity of concrete and the complex interaction with steel reinforcement. Existing finite element (FE) approaches are restricted to simplified 2D representations, depend on predefined crack paths, or do not incorporate the material heterogeneity of RC in three dimensions. This study presents a 3D FE framework in Abaqus to model the cracking behaviour of RC tie elements, combining a phase field formulation with stochastic random fields (RF) to represent spatial variability in tensile strength and fracture toughness. Parametric studies demonstrate the influence of key modelling parameters, including the phase field length scale, solution scheme, and correlation length of the RF. The numerical results are validated against experimental data from RC tie tests in the literature, and demonstrate good agreement in the global load–displacement response and localised crack patterns. The study shows that the proposed approach is a robust predictive tool able to capture the uncertainty arising from local material heterogeneity, and can simulate diverse crack initiation and propagation scenarios in RC; The authors acknowledge the support provided by the Spanish Ministry of Science, Innovation and Universities (MICIU/AEI) through the project PID2023-150934NB-C32/MICIU/AEI/10.13039/501100011033/FEDER, UE; M.B. acknowledges the support provided by the Agency for Management of University and Research Grants (AGAUR) Generalitat de Catalunya resolution REU/551/2022 for the support grants for university departments and research units aimed at the recruitment of pre-doctoral research staff in training in Catalonia (FI-SDUR 2022) ref. BDNS 612831; L.C. acknowledges the grant RYC2021-032171-I funded by MCIN/AEI/10.13039/501100011033 and by “European Union NextGenerationEU/PRTR ”. Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevier. 2026-02-21T00:00:00Z https://hdl.handle.net/10256/28405 Fatigue behavior of externally bonded and hybrid-bonded carbon fiber reinforced polymer–to–concrete joints Aghabagloo, Mehdi; Carreras Blasco, Laura; Sena-Cruz, José; Baena Muñoz, Marta Although the bond behavior and failure modes of externally bonded reinforcement (EBR) fiber-reinforced polymer (FRP) and hybrid-bonded (HB) systems on concrete have been widely investigated under quasi-static loading, their performance under fatigue loading remains insufficiently understood. Existing research on RC structures strengthened with carbon FRP (CFRP) under cyclic loading has predominantly focused on demonstrating improvements in fatigue life. However, far less attention has been given to examining the bond behavior and the rate of debonding growth, factors that are critical to ensuring the long-term effectiveness and durability of externally bonded CFRP systems. This study experimentally examines the performance of EBR and HB CFRP-to-concrete bonded joints subjected to cyclic fatigue loading. The investigation focuses on the progression of fatigue-induced damage in bonded joints tested under direct pull-out conditions, using CFRP laminates exposed to different maximum cyclic load levels (relative to the static failure load) while keeping a constant load ratio. Under fatigue loading, interfacial debonding between the CFRP laminate and the adhesive was observed, whereas quasi-static tests typically resulted in cohesive failure within the concrete. Results also revealed that increasing the maximum cyclic load markedly accelerated the rate of debonding propagation; The authors acknowledge the support provided by the Spanish Ministry of Science, Innovation and Universities (MICIU/ AEI) through projects PID2020-119015GB-C22/MICIU/AEI/10.13039/501100011033 and TED2021-132198B-I00/ MCIN/AEI/10.13039/501100011033, UE; L.C. acknowledges the grant RYC2021-032171-I funded by MCIN/AEI/ 10.13039/501100011033 and by “European Union NextGenerationEU/PRTR. The authors wish to acknowledge the support of S&P Clever Reinforcement Ibérica Lda for supplying the laminates and the epoxy adhesive used in this study. Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevier 2026-05-01T00:00:00Z https://hdl.handle.net/10256/28206 Probability Distribution of Turbulent Kinetic Energy Dissipation Rate in Ocean: Observations and Approximations Lozovatsky, Iossif; Fernando, Harindra Joseph S.; Planella Morató, Jesús; Liu, Zhiyu; Lee, J-H.; Jinadasa, S.U.P. The probability distribution of turbulent kinetic energy dissipation rate in stratified ocean usually deviates from the classic lognormal distribution that has been formulated for and often observed in homogeneous layers of atmospheric and oceanic turbulence. Our microstructure measurements, collected in the East China Sea, northern Bay of Bengal, to the south and east of Sri Lanka, and in the Gulf Stream region, show that the probability distributions of the dissipation rate in stably stratified layers can be successfully modeled by the Burr (type XII) probability distribution. In weakly stratified boundary layers, lognormal distribution of the dissipation is preferable, although the Burr is an acceptable alternative; Research funding: US Office of Naval Research . Grant Numbers: N00014-13-1-0199 , N00014-14-1-0279 , N00014-05-1-0245 , N00014-17-1-3195 NPS . Grant Number: N00244-14-2-0004; National Natural Science Foundation of China . Grant Numbers: 41476006 , 41622601 & Korean Institute of Ocean Science and Technology . Grant Number: E99513 2017-10-01T00:00:00Z https://hdl.handle.net/10256/28205 Heat flux through a geothermally heated fluidized bed at the bottom of a lake Sánchez Martín, Xavier; Roget, Elena; Planella Morató, Jesús Heat fluxes and the underground inflow through a natural fluidized bed within the main sub-basin of Lake Banyoles are studied and parameterized. In the upper part of this fluidized bed, at a depth of about 30 m, the vertical gradients of particle concentration and temperature are very sharply located within an interface a few centimeters thick. Within this interface (lutocline), the depths where the temperature and the concentration gradients are maximum match exactly. On the other hand, the lutocline determines a flat, horizontal surface dividing the water column into a hot, turbid medium at the bottom and clear, colder, bulk water above. Through this interface the flow regime also varies from being laminar just below it, to turbulent due to convective processes developing above it. More precisely, in studied main sub-basin a buoyant plume develops above the lutocline, as a result of the heat flux, and affects the lake's water quality due to particles dragged along by it. In this paper it is proposed to determine the temperature at the depth of maximum gradient within the interface by means of measured temperature profiles, and consider the stationary heat transport equation in the laminar region below it, in order to obtain the water velocity and the heat flux. Heat flux parameterization is given based on a large number of thermal high-resolution profiles, covering six campaigns in different years and seasons. Furthermore, and in consideration of the fact that high-resolution thermal profiles are not always available, some alternative parameterizations for the heat flux are presented based only on the temperature of the fluidized bed and that of the lower hypolimnion; This work has been partly supported by the FIS2008-03608 project of the Spanish Science and Innovation Ministry 2009-07-01T00:00:00Z