Durability of bond of EBR CFRP laminates to concrete under real-time field exposure and laboratory accelerated ageing

The durability of bond between carbon fibre-reinforced polymer (CFRP) laminates and concrete with the externally bonded reinforcement (EBR) technique was investigated under real-time field exposure (RTFE) and accelerated ageing. The experimental program, over two years, includes four outdoor environments inducing carbonation, freeze–thaw attack, extreme temperatures, and airborne chlorides from the ocean. A laboratory environment (20 ◦C/55% RH) was used as reference environment. Additionally, a water-immersion environment (20 ◦C) was also considered. Relatively low values of bond degradation were observed, where the maximum pullout force varied between − 4 % and +16 % under RTFE, while on water–immersed specimens, the maximum pullout force decreased by ~8 %.This work was carried out in the scope of the project FRPLongDur POCI-01-0145-FEDER-016900 (FCT PTDC/ECM-EST/1282/2014) and DURABLE-FRP (PTDC/ECI-EGC/4609/2020) funded by national funds through the Foundation for Science and Technology (FCT) and co-financed by the European Fund of the Regional Development (FEDER) through the Operational Program for Competitiveness and Internationalization (POCI) and the Lisbon Regional Operational Program and, was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020, and under the Associate Laboratory Advanced Production and Intelligent Systems ARISE under reference LA/P/0112/2020. The first author wishes also to acknowledge the grant SFRH/BD/131259/2017 provided by Fundação para a Ciência e a Tecnologia (FCT)

Seminário de conclusão do projeto FRPLongDur

The FRPLongDur research project (reference no. POCI-01-0145-FEDER-016900) was financed by national funds through FCT and co-financed by the European Regional Development Fund (FEDER) through the Competitiveness and Internationalization Operational Program (POCI), and Lisbon Regional Operational Program. This project had as participating institutions at the University of Minho and the National Civil Engineering Laboratory. It also had the participation of Empa - Swiss Federal Laboratories for Materials Science and Technology. FRPLongDur aimed at contributing to the knowledge on the long-term behavior and durability of reinforced concrete elements strengthened with CFRP (Carbon Fiber Reinforced Polymers) laminates according to the EBR (Externally Bonded Reinforcement) and NSM (Near Surface Mounted) reinforcement techniques, under the effect of aging in real environments. The work involved: (i) an extended experimental program, with the creation of five experimental stations distributed throughout Portugal country, involving different environments (Elvas, Guimarães, Lisbon, Serra da Estrela and Viana do Castelo), where test specimens at three scales (material, connection and structure) were installed to evaluate its performance during the time; (ii) the development of numerical simulations, based on the results obtained in the monitoring carried out; and, (iii) making recommendations for the project. On the last 30th of October 2020, the seminar to conclude the FRPLongDur project took place in a Webinar mode, in which the main results were presented. The present eBook summarizes the presentations carried out

Conceptualization of rice with low glycemic index: perspectives from the major european consumers

Rice and cereal consumption has become a concern for consumers due to usually high glycaemic indexes (GI), which is a critical issue for a balanced and healthy diet. Therefore, the development of new products with low GI is an important target of the industry, particularly in countries with high consumption. This study assesses consumers’ perceptions about “rice” and “rice with low GI” and evaluates the effect of consumers’ rice consumption profiles through the application of a free word association technique in a structured self-administered electronic questionnaire with 256 Portuguese consumers (the European market with the highest per capita consumption of rice by far). The frequency of rice consumption was evaluated, and the consumption profile was determined through a hierarchical cluster analysis, with 9% identified as daily consumers. The response words were categorized by the triangulation technique, and the association between the word categories and dimensions, sociodemographic characteristics, and consumption profile were determined. Respondents most frequently associated “rice” with rice dishes, its sensory attributes, and nutrition, highlighting the satisfaction of nutritional and hedonic needs. Consumers revealed positive expectations in relation to the functionality of “rice with low GI”. The consumers’ rice consumption profiles, sex, age, and educational levels influenced their perception towards “rice“ and “rice with low GI”. This study provides important insights for the industry to develop a consumer-oriented, low GI rice product.: This research was funded by the Foundation for Science and Technology (FCT) through D. Cabral’s Doctoral grant no. SFRH/BD/146895/2019, as well as the project Arroz BIG—Development of rice products with low glycaemic index (POCI-01-0247-FEDER-017931), funded by COMPETE2020, Portugal2020, Norte2020, and FEDER-European Regional Development Funds. This work was also supported by national funds from the FCT through the research unit GreenUPorto (UIDB/05748/2020 and UIDP/05748/2020).info:eu-repo/semantics/publishedVersio

Durability of epoxy adhesives and carbon fibre reinforced polymer laminates used in strengthening systems: accelerated ageing versus natural ageing

This work addresses the durability of structural epoxy adhesives and carbon fibre reinforced polymer (CFRP) laminates typically used in strengthening of existing reinforced concrete structures exposed to natural ageing. The experimental program included four natural (real) outdoor environments inducing ageing mainly caused by carbonation, freeze-thaw attack, elevated temperatures, and airborne chlorides from seawater. Moreover, a control (reference) environment (20 °C of temperature and 55% of relative humidity) and an environment involving water immersion of the materials under controlled temperature (20 °C of temperature) were also included in this investigation. The characterization involved the assessment of the physical, chemical and mechanical properties along a study period of up to two years. Furthermore, comparisons between the natural ageing tests developed in the scope of the present work and accelerated ageing tests existing in the literature were performed. Regarding to the epoxy adhesives, an increase in the glass transition temperature with the time was observed, while the tensile properties decreased, regardless of the outdoor environment. The CFRP laminates were marginally affected by the studied environments. Despite the remarkable dispersion of the results observed in the accelerated ageing tests for the period investigated, this testing protocol yielded higher mechanical degradation than under natural ageing.This work was carried out in scope of the project FRPLongDur POCI-01-0145-FEDER016900 (FCT PTDC/ECM-EST/1282/2014) funded by national funds through the Foundation for Science and Technology (FCT) and co-financed by the European Fund of the Regional Development (FEDER) through the Operational Program for Competitiveness and Internationalization (POCI) and the Lisbon Regional Operational Program and, partially financed by the project POCI-01-0145-FEDER007633, and partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020. This work is financed by national funds through. Foundation for Science and Technology, under grant agreement (SFRH/BD/131259/2017) attributed to the first author

Analytical prediction of flexural behaviour of RC slabs strengthened with non-prestressed and prestressed CFRP strips

The flexural behaviour of reinforced concrete (RC) slabs strengthened with carbon fibre reinforced polymer (CFRP) laminates is analytically addressed in this work. Analytical approaches are developed for (i) near-surface mounted (NSM), (ii) externally bonded reinforcement (EBR), and the EBR prestressed using (iii) mechanical anchorage (MA) and (iv) gradient anchorage (GA) systems. The analytical results show a good agreement with those from experimental program. Besides, the performance of two existing formulae for predicting the mid-span deflection is assessed, and the performance of the recent fib Bulletin 90 technical report for predicting the ultimate capacity of the strengthened RC slabs is appraised.This work was carried out in scope of the project FRPLongDur POCI-01-0145-FEDER-016900 (FCT PTDC/ECM-EST/1282/2014) and Durable-FRP (PTDC/ECI-EGC/4609/2020) funded by national funds through the Foundation for Science and Technology (FCT) and co-financed by the European Fund of the Regional Development (FEDER) through the Operational Program for Competitiveness and Internationalization (POCI) and the Lisbon Regional Operational Program. This work was partly financed by FCT / MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB / 04029/2020. This work is financed by national funds through FCT under grant agreement [DFA/BD/08403/2021] attributed to the first author

Durability of CFRP-concrete bond and corresponding involved materials under different natural environmental exposures for a period of four years

Ageing of interfaces between Carbon Fibre Reinforced Polymer (CFRP) laminates and concrete, applied according to externally bonded reinforcement (EBR) and near-surface mounted (NSM) techniques, and their constitutive materials was investigated. That is, experimental tests on the ageing of concrete, epoxy adhesive, CFRP laminate, and the CFRP-concrete interface were performed for specimens after being exposed to different natural outdoor environments to promote degradation due to carbonation, chlorides, freeze-thaw attacks, and high temperatures. Besides, tests of the reference specimens, kept under a control environment of 20 °C and 55% RH, and of specimens continuously immersed in water with a controlled temperature of 20 °C were also included for comparison purposes. The characterization of physical and mechanical properties of the involved materials, and the degradation of CFRP-concrete interface for the specimens strengthened according to EBR and NSM techniques were assessed for a study period of up to four years. The results generally showed significant variations in the properties of the concrete and adhesive while the ageing of CFRP was found insignificant in all the studied environments. Besides, slight variations of the bond strength were observed, probably as a result of changes in the constitutive materials’ mechanical properties with time and environmental exposure

Spatial Variation in Mercury Bioaccumulation and Magnification in a Temperate Estuarine Food Web

Estuaries are renown sinks or repositories of contaminants and reflect historical pollution of persistent compounds. In particular, mercury (Hg) contamination is widespread in coastal environments and occurs in both inorganic (THg) and highly toxic organic forms (OHg) with high bioaccumulation potential. Trophic magnification factors have been increasingly used to quantify biomagnification and represent the average rate of change in contaminant concentration throughout a food web. Here, we assessed small-scale spatial variation in THg and OHg concentrations, as well as variations in local trophic magnification factors in three segregated areas of the Tejo estuary. Selected sites covered a gradient of contamination from industrial Hg hotspots to a natural reserve area, and are key nursery areas for multiple fishes. We analyzed concentrations in sediment and biota, representing the entire local food webs. Samples included sediments, primary producers (salt marsh plants), primary consumers (macrobenthic invertebrates) and top consumers (fish muscle and liver), and the trophic web structure was characterized via SIAR mixed-modeling of nitrogen and carbon isotopic ratios. Spatial variation in Hg concentrations was observed in sediment and biota (but not for all species), with highest concentrations in the area near historical mercury input. Hg concentrations increased with trophic level, and so did the OHg fraction (% of OHg relative to THg), with mean maximum values up to 48.7 and 94.9% in invertebrates and fish, respectively. Trophic magnification factors were positive for all sites (p < 0.05 for all regressions), ranging between 1.56 to 1.76 and 1.78 to 2.47 for THg and OHg, respectively. Overall, rates of mercury bioaccumulation were similar across sites with variations in biota Hg concentrations reflecting baseline differences in site environmental levels. Understanding mercury bioaccumulation and magnification in estuarine biota is critical to safeguard the multiple ecologic functions and economic benefits estuaries provide.info:eu-repo/semantics/publishedVersio

The Eastern Lower Tagus Valley Fault Zone in central Portugal : active faulting in a low-deformation region within a major river environment

Active faulting in the Lower Tagus Valley, Central Portugal, poses a significant seismic hazard that is not well understood. Although the area has been affected by damaging earthquakes during historical times, only recently has definitive evidence of Quaternary surface faulting been found along the western side of the Tagus River. The location, geometry and kinematics of active faults along the eastern side of the Tagus valley have not been previously studied. We present the first results of mapping and paleoseismic analysis of the eastern strand of the Lower Tagus Valley Fault Zone (LTVFZ). Geomorphological, paleoseismological, and seismic reflection studies indicate that the Eastern LTVFZ is a left-lateral strike-slip fault. The detailed mapping of geomorphic features and studies in two paleoseismic trenches show that surface fault rupture has occurred at least six times during the past 10 ka. The river offsets indicate a minimum slip rate on the order of 0.14–0.24 mm/yr for the fault zone. Fault trace mapping, geomorphic analysis, and paleoseismic studies suggest a maximum magnitude for the Eastern LTVFZ of Mw ~ 7.3 with a recurrence interval for surface ruptures ~ 1.7 ka. At least two events occurred after 1175 ± 95 cal yr BP. Single-event displacements are unlikely to be resolved in the paleoseismic trenches, thus our observations most probably represent the minimum number of events identified in the trenches

IL-31 and IL-8 in Cutaneous T-Cell Lymphoma: Looking for Their Role in Itch

The itch associated with cutaneous T-cell lymphoma (CTCL), including Mycosis Fungoides (MF) and Sézary syndrome (SS), is often severe and poorly responsive to treatment with antihistamines. Recent studies have highlighted the possible role of interleukins in nonhistaminergic itch. We investigated the role of IL-31 and IL-8 in CTCL, concerning disease severity and associated itch. Serum samples of 27 patients with CTCL (17 MF and 10 SS) and 29 controls (blood donors) were analyzed for interleukin- (IL-) 31 and IL-8; correlations with disease and itch severity were evaluated. IL-31 serum levels were higher in CTCL patients than in controls and higher in SS than in MF. Also, serum IL-31 levels were higher in patients with advanced disease compared to those with early disease, and they correlated positively with lactate dehydrogenase and beta 2-microglobulin levels, as well as with the Sézary cell count. Itch affected 67% of CTCL patients (MF: 47%; SS: 100%). Serum IL-31 levels were higher in itching patients than in controls and in patients without itching. There was no association between serum IL-8 and disease severity, nor with itching. Serum IL-8 levels correlated positively with peripheral blood leukocyte and neutrophil counts in CTCL patients. Our study suggests a role for IL-31 in CTCL-associated itch, especially in advanced disease and SS, offering a rational target for new therapeutic approaches. Increased serum IL-8 observed in some patients may be related to concomitant infections, and its role in exacerbating itch by recruiting neutrophils and promoting the release of neutrophil proteases deserves further investigationinfo:eu-repo/semantics/publishedVersio

Spatial Variation in Mercury Bioaccumulation and Magnification in a Temperate Estuarine Food Web

Estuaries are renown sinks or repositories of contaminants and reflect historical pollution of persistent compounds. In particular, mercury (Hg) contamination is widespread in coastal environments and occurs in both inorganic (THg) and highly toxic organic forms (OHg) with high bioaccumulation potential. Trophic magnification factors have been increasingly used to quantify biomagnification and represent the average rate of change in contaminant concentration throughout a food web. Here, we assessed small-scale spatial variation in THg and OHg concentrations, as well as variations in local trophic magnification factors in three segregated areas of the Tejo estuary. Selected sites covered a gradient of contamination from industrial Hg hotspots to a natural reserve area, and are key nursery areas for multiple fishes. We analyzed concentrations in sediment and biota, representing the entire local food webs. Samples included sediments, primary producers (salt marsh plants), primary consumers (macrobenthic invertebrates) and top consumers (fish muscle and liver), and the trophic web structure was characterized via SIAR mixed-modeling of nitrogen and carbon isotopic ratios. Spatial variation in Hg concentrations was observed in sediment and biota (but not for all species), with highest concentrations in the area near historical mercury input. Hg concentrations increased with trophic level, and so did the OHg fraction (% of OHg relative to THg), with mean maximum values up to 48.7 and 94.9% in invertebrates and fish, respectively. Trophic magnification factors were positive for all sites (p &lt; 0.05 for all regressions), ranging between 1.56 to 1.76 and 1.78 to 2.47 for THg and OHg, respectively. Overall, rates of mercury bioaccumulation were similar across sites with variations in biota Hg concentrations reflecting baseline differences in site environmental levels. Understanding mercury bioaccumulation and magnification in estuarine biota is critical to safeguard the multiple ecologic functions and economic benefits estuaries provide