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This study presents the characterization and chronology of the Quaternary terrace sequence developed in the confluence zone of the Júcar and Cabriel river valleys. The study area covers a radius of 10 km from the confluence of the two valleys near the locality of Cofrentes (Valencia). It is located in the northern zone of the Ayora-Cofrentes Graben in the northeastern sector of the External Prebetic Zone adjacent to southern Iberian Chain. This N-S graben is an inherited tectonic feature with an axial salt wall subject to different periods of fluvial dissection and refilling since at least the end of the Messinian Salinity Crisis (MSC). Regional isostatic uplift and local uplift and subsidence processes related to salt flow and dissolution during the Quaternary period, favored by fluvial entrenchment and terrace development. The terrace system and the previous pre-incision erosional and depositional surfaces are analyzed from a geomorphological point of view. The terrace system only develops within the soft Mio-Pliocene sedimentary fill of the graben, whilst upstream and downstream this zone the studied valleys develop important gorges (canyons) carved in the Cretaceous tablelands (Caroch Massif) and Mio-Pliocene deposits (Llanura Manchega). The geochronological control is established from 20 numerical ages obtained by different dating methods, such us Electron Spin Resonance (ESR), Optically Stimulated Luminescence (OSL) in detrital sequences and Th/U series in calcareous tufa deposits. Additionally, four K/Ar dates available for volcanic materials disrupting the upper and oldest terrace have been considered. A total of 14 terrace levels were identified between +130–135 m (T1) and +3–4 m (T14) of relative height above the river thalwegs. The T1 has an approximate age of c. 1.6–2.0 M.a. as indicate the age of the volcanic materials from the Agras Volcano intruded in the terrace, marking the onset of Quaternary fluvial dissection in the zone. The obtained geochronological data indicate that the Lower-Middle Pleistocene boundary is slightly above T6 (+60–65 m), which has an ESR age of 577 ± 43 ka. This terrace also documents the onset of the most important period of rise of the salt within the graben interfering drainage development. The geochronological data indicate the occurrence of a second eruptive event during the second half of the Middle Pleistocene related to the terraces T7 (+50 m) and T8 (+35–40 m), updating the volcanic activity in the zone. The beginning of the Upper Pleistocene is recorded by the top sequences of the T9 terrace (+25–30 m) where numerous OSL and Th/U data have been obtained with ages between ca. 105 and 81 ka (MIS 5). However, these young terraces (T8 to T13) are thickened (8–10 m) recording Middle Pleistocene sediments in their basal sequences with ages between ca. 193 and 137 ka (MIS 6). The study provides important data on valley evolution under the interference of volcanic activity, salt –related deformation (diapirism, solution subsidence) and fluvial incision fostered by the rise of the axial diapir (salt wall) protruding the graben since at least the Brunhes-Matuyama boundary. The analyzed fluvial evolution documents interesting cases of river capture, drainage antecedence and tectonic adaptation of the drainage throughout the Quaternary Period. The paper also poses interesting geochronological data on the long-term Quaternary evolution of Mediterranean valleys in the Iberian Peninsula, poorly explored to the date. [Display omitted] • The evolution of the Júcar Fluvial system (Spain) is addressed for first time supported. • The catchment contains a complex sequence of 14 terrace levels up to +135 m • Terrace sequence is dated within the last 2.0 Ma using K/Ar, Th/U, OSL and ESR data. • Phreatomagmatic activity disrupts valley evolution during the Lower-Middle Pleistocene • Cases of river capture, drainage antecedence and tectonic superposition are documented [ABSTRACT FROM AUTHOR]

The structural fire analysis of bridges is crucial for ensuring transportation infrastructure safety since bridges, due to their unique characteristics and exposure to environmental hazards, are particularly susceptible to fire-induced damage. Despite this vulnerability, there is a lack of both experimental research and design guidelines for ensuring fire safety in bridges. This underscores the importance of studying actual bridge fire incidents. This article presents a comprehensive examination of the numerical and experimental investigations carried out to evaluate the structural condition of a composite box-girder bridge located in Valencia, Spain, following a significant fire incident. In addition, the paper details the repair works carried out to fully restore the operational capacity of the bridge, along with the key lessons learnt from the incident. Therefore, the article highlights the vital synergy between advanced numerical models and experimental investigations to strengthen rehabilitation action plans and gain valuable insights for making informed decisions regarding post-fire structural integrity. By doing so, the study enhances understanding of bridge safety under fire and provides actionable recommendations for researchers, practitioners, and transportation authorities. • There is a lack of guidelines on the assessment of bridges vis-à-vis fire hazards. • Effects of a real fire on a bridge examined with numerical and experimental methods. • Repair works and lessons learned from the incident are detailed. • Synergies of numerical models and experiments strengthens rehabilitation planning. • Fire safety insights and informed decision-making for bridge resilience enhanced. [ABSTRACT FROM AUTHOR]

• A real case of fatigue failure in a heritage element has been studied. • The collapse has occurred after 300,000 operating cycles after the 1992 restoration. • Metallographic, hardness and mechanical analyzes coincide on the steel characteristics. • Analytical and numerical analysis validate that the collapse was due to fatigue. • The effect of the stress concentrator and surface finish has been critical in failure. • A new steel shaft gudgeon has designed for all the bells restored in 1992. This paper describes the collapse analysis of the historical El Jaume bell, cast in 1429, one of the bells in the Cathedral of Valencia's Micalet bell tower (Spain). In 1992 the yoke was completely restored and given a new steel axis. The failure occurred when the bells were being rung on Christmas Day 2014, fortunately without any casualties. After several field visits to assess the damage and failure "in situ", a diagnosis was made of the causes of the failure. The diagnosis was the result of (1) a detailed visual inspection, (2) a metallographic and fractographic analysis of the fractured steel axis, (3) a fatigue damage analysis by finite element modelling software and (4) an estimation of the bell's remaining fatigue life cycle using Whöler S-N curves. In view of the results obtained it was concluded that the fatigue life cycle should have been reached between 300,000 and 400,000 cycles, while the failure occurred at 346,500 cycles. Although these elements are usually designed to not fail during its life, they can sometimes suffer cracks during cyclic ringing. One of the main causes of the fatigue failure was the incorrect design of the steel gudgeon, which produced a high stress concentration and drastically reduced the fatigue strength at 106 cycles. The paper also describes the remedial measures taken to avoid fatigue failure in the other bells and the lessons that have been learned from the experience. [ABSTRACT FROM AUTHOR]

• This study calibrates simplified and advanced numerical models of bridge fires. • Calibrated from the results of the Valencia bridge fire tests. • Simplified models have serious limitations regarding the fire load. • Uncertainty studies prove the goodness of the advanced models using CFDs. • The study is an important step towards a performance-based approach to bridge fires. Bridge fires are a major concern and the subject of many studies that use numerical models. However, experimental studies are still required to test the validity of these numerical models and improve their accuracy. This paper uses temperature results of the Valencia bridge fire tests carried out at the Universitat Politècnica de València, in Valencia (Spain) to calibrate the fire models that constitute the first step in modeling any bridge fire event. The calibration is carried out by both a simplified approach (Heskestad and Hamada's correlation) and advanced numerical models (Computational Fluid Dynamics models built with the Fire Dynamics Simulator –FDS- software). The Valencia bridge fire tests involved four fire scenarios under a composite bridge with Heat Release Rate (HRR) values between 361 and 1352 kW. The results show that applying Heskestad and Hamada's correlation gave good results when used within its limits of application (HRR < 0.764 MW) but did not work well beyond them, which means it would be suitable for planning reduced scale bridge fire tests but not in the analysis of real bridge fires. On the other hand, FDS provides good predictions of the temperatures and can be used to study bridge fire responses. This work is therefore an important step forward in the study of bridge fires and towards the improvement of the resilience of infrastructure networks vis-à-vis fire hazards. It also highlights the problems that can arise in fire tests in the open air, the influence of the wind being of critical importance. [ABSTRACT FROM AUTHOR]

The European SHERPA project aims to share knowledge for energy renovation in buildings by public administrations. The EU Energy Performance in Buildings Directive (EPBD) recast, indicates the necessity of transforming EU buildings into Nearly Zero Energy Buildings (nZEB). Each Member State transposes differently the EPBD, usually based on European norms like Spain did. The generated knowledge about improving performance and transforming public buildings into nZEBs, is applied here to schools, according to the Spanish transposition. SHERPA, among other buildings, has audited four schools sited in the Valencia Region (Spain, Southern European Country). The paper starts describing, briefly, the general auditing protocol devised by SHERPA. Particularly, one school was chosen out of the four to illustrate the protocol and was converted into a nZEB. This school led to the most unexpected and outstanding results, although the trends were shared among all the audited schools. Finally, based on the results, the paper suggests some recommendations to the policy makers about the practical definition of nZEB and financial instruments to engage this nZEB challenge for schools. [ABSTRACT FROM AUTHOR]

• The specific contribution of GUAs to the SDGs has been analysed. • Green urban areas contribute directly to the achievement of SDG11, SDG15 and SDG13. • Equity in sustainable development has been assessed at a sub-neighbourhood level. • Equity requires an adequate location, size, quantity and quality of GUA. The Agenda for Sustainable Development 2030 of United Nations is made up of the 17 Sustainable Development Goals (SDGs) that humanity will have to meet by 2030. In achieving the SDGs, green urban areas (GUA) play a fundamental role at the local level as they provide recreational and bioclimatic regulatory functions and act as a carbon sink, as well. Specifically, the GUAs contribute directly to three SDGs: SDG 11 Sustainable cities and communities, SDG 13 Climate Action and SDG 15 Life on land. This paper evaluates direct contribution of GUA to this SDGs with high spatial resolution in the case study of the city of Valencia (Spain). The evaluation carried out has made it possible to make a diagnosis of the quantity and accessibility of GUA at sub-neighbourhood level. The results for SDG 11 show that only 9.23% of the population do not have desirable access to GUA and 2.73% live in areas without easy walking distance access to GUA. On the other hand, the evaluation of SDG 15 shows that each inhabitant has at their disposal 10 m2 of GUA, below the average of cities of more than 250,000 inhabitants in Spain. The high spatial resolution of the evaluation has also made it possible to identify the city areas with the worst access to GUA and the least amount of GUA per inhabitant. In consequence, the results allow determining zones with high potential to improve. Additionally, the quantification of the CO 2 fixed by the GUA carried out for the evaluation of SDG 13, shows that the fixed carbon is equivalent to 0.04% of total gross GHG emissions of the city and is 36% higher than the total GHG emissions of the annual fuel consumption of the total fleet in the city. Finally, the monitoring of the indicators applied allows evaluating the evolution of the GUA to improve the sustainable development of the city. [ABSTRACT FROM AUTHOR]

Abstract: Numerous computer programs are available to calculate the energy efficiency of buildings. Many are based on the use of a reference building to determine the degree of efficiency. However, this methodology presents a major constraint when assessing a building after construction and during the use stage. To assess the energy efficiency of buildings, this paper proposes new indices based on energy consumption during different periods; as well as other parameters of the buildings such as construction area, number of users, and air-conditioned volume. Results are presented as an application for various buildings on the campus of the Universidad Politécnica de Valencia. [ABSTRACT FROM AUTHOR]

This paper describes a double experimental and analytical study of the fatigue behaviour of the Quisi and Ferrandet Bridges, twin 170 m long steel railway bridges constructed between 1913 and 1915 with typical Pratt truss structures and riveted connections. These bridges are part of the Spanish national railway network connecting the towns of Alicante and Denia, one of the key networks in the Valencia Region (Spain). The experimental laboratory investigation involved fatigue testing in one of the ICITECH laboratories at the Universitat Politècnica de València of: (i) a full-scale bridge span and (ii) an upper cross beam from the Ferrandet Bridge. During the tests, Linear Variable Displacement Transducers (LVDTs) and Strain Gauge (SG) sensors were used to capture the possible nucleation and propagation of fatigue cracks. Fatigue test carried out on the cross beam identified: (i) fatigue life of the critical detail, (ii) fatigue hot-spots along the cross beam and (iii) strain redistribution along the riveted element during crack growth. The experimental results from the full-scale bridge were adopted to calibrate an elastic numerical model of the whole structure, which was in turn used to estimate the Quisi Bridge's remaining fatigue life. The definition of the class of detail and remaining fatigue life were calculated by the S–N curves method, according to Eurocode 3, considering the available information on the bridges' loading histories. [Display omitted] • An integrated multi-field analytical method for prediction of the residual fatigue life of steel bridges is proposed. • Double fatigue lab investigation on: (i) upper cross beam; (ii) isostatic span. • S N curves method provided detail classes of 63 or 71 for the girder element.. • Strain gauges were able to track the redistribution of stresses as cracks grew. • The fatigue test of the isostatic span lasted 45 k cycles confirming that the bridge could operate safely for 27 years more. [ABSTRACT FROM AUTHOR]

• Shadow cast vector-based model implemented in a 2D-GIS environment. • Best statistical indicators for building height are robust mode estimators. • 3D building model and shadow model validated accurately. • Maximum error in overall, including both height and shadow models, lower than 2% • Wide range of applications, particularly in Solar Resource Assessments. This paper presents a systematic GIS-based methodology to obtain the shadow cast profile of a group of buildings on arbitrarily orientated and tilted surfaces. The model is integrated in the widely-employed 2D-GIS environment. Given its scalability, the methodology can be easily applied from a local level up to a district, city or even regional level. This work is of interest for a wide range of applications such as for instance in Solar Resource Assessments (SRA) in urban environments. The starting point is to use cadastral cartography and LiDAR altimetric data to obtain a 3D vector-based model of the buildings using high robust mode estimators. Once the geometry of the buildings is defined, analytical models are applied to calculate the shadow cast profile on any arbitrarily orientated and tilted surface of the surroundings. The model has been implemented in the R programming language. An extensive validation has been carried out for several buildings of Valencia (Spain) using CAD elevation views of the buildings and the SketchUp's shadow tool. The error of the vector-based city model is lower than 1% in all LiDAR datasets. The maximum error of the overall methodology, including both height and shadow models, is lower than 2%. [ABSTRACT FROM AUTHOR]

• A specific degradation analysis of elevated storage tanks is developed. • On-desk study, on-site survey, diagnostic approach and ranking are defined. • 32 case studies in Valencia are analysed. • Frequent damage and the related causes are identified. • Best maintenance and intervention strategies are proposed. Assessing the condition of existing structures, with a particular focus on analysing the degradation level, is a complex issue for those responsible for maintenance and monitoring. Elevated storage tanks (water towers) are particularly prone to suffering obsolescence and degradation. As many of these structures are no longer in use and in a poor state of conservation, researchers and local administrators need new tools to achieve a complete overview of the tank condition on a regional scale with limited resources. This paper presents a large-scale structural degradation analysis on the specific structural typology of storage tanks. Firstly, the tanks performances and degradation level are analysed by using a multicriteria approach useful to include both qualitative and quantitative data in the analysis. Secondly, 32 case studies in Valencia (Spain) are investigated to demonstrate the method's potential. Thirdly, the results of the degradation analysis were used to identify the most frequent damage, the related causes and the structures in the worst conditions. Finally, the best maintenance and intervention strategies to extend the tanks' remaining life and protect them from further damage are proposed. [ABSTRACT FROM AUTHOR]

The introduction of hybrid electric technology for urban public transportation can be considered a valuable stepping stone to low-carbon mobility. Using the contingent valuation method, a sample of 427 respondents were asked about their willingness to pay for the air pollution reductions associated to a scenario of gradual introduction of hybrid electric buses in Valencia, Spain. Results show that 67% of the respondents are willing to pay extra for the adoption of this electric hybrid technology, being the mean willingness to pay € 0.33 per single bus fare. This would imply a 22% hypothetical increase in current bus fares and shows that public acceptance is critical for the successful introduction of these new low-emissions vehicles. Further, this paper differs from previous research in that it addresses the issue of heterogeneity among respondents. Thus, using latent class analysis, based on questions about environmental concerns, we identify three different classes of respondents: high, medium and low environmentally concerned. Mean willingness to pay for each class ranges from €0.25 to €0.38. Then we analyze willingness to pay determinants through the estimation of a Tobit model for each class of respondents. This reaffirms the existence of heterogeneity and accordingly suggests that treating the population as a single homogeneous group of respondents, as is common in the existing literature, may lead to biased parameter estimates and flawed decision-making regarding climate change action. Image 1 • Public acceptance of hybrid buses is analyzed in a Contingent Valuation scenario. • Preference heterogeneity is investigated using a Latent Class Model. • Results show a high level of heterogeneity among respondents. • Mean willingness to pay for each class of respondent is estimated. [ABSTRACT FROM AUTHOR]