Determinación teórica y experimental de diagramas de interacción de esfuerzos en estructuras de fábrica y aplicación al análisis de construcciones históricas

Se propone una metodología de análisis para construcciones históricas de fábrica basada en el Método de los Estados Límite, haciendo uso de diagramas de interacción de esfuerzos, de forma similar a la práctica habitual en hormigón estructural o acero, pero incorporando las peculiaridades mecánicas del material estudiado. La tesis presenta la construcción teórica de los diagramas y la campaña experimental desarrollada para el contraste de la teoría. Se muestran los resultados de ensayos sobre probetas y muretes de fábrica de ladrillo sometidas a distintas combinaciones de esfuerzos planos, axil, momento y cortante. En los ensayos se detecta un fenómeno no recogido anteriormente en la literatura, consistente en una significativa sobre resistencia de la fábrica sometida a axiles excéntricos en su plano. Se presentan estudios numéricos de micromodelo que aclaran la naturaleza del fenómeno. Se incluyen tres ejemplos de aplicación de las técnicas propuestas a casos reales desarrollados sobre construcciones históricas de fábrica: La Catedral de Palma de Mallorca, el refuerzo y la ampliación de un puente de bóvedas del s. XIX en La Coruña y una cúpula barroca colapsada en 2000 en Zaragoza

Perceptions and Acceptance of Desalinated Seawater for Irrigation: A Case Study in the Níjar District (Southeast Spain)

In the context of increasing demand for irrigation water—but, at the same time, with the constraints in the supply from traditional resources—desalinated seawater has been recognized as one of the alternative sources of water to increase the supply for agricultural irrigation. However, its use among farmers has not yet started to expand. Policy makers need to understand what is causing the low acceptance levels of farmers, and how their attitudes could be improved. This is the first study that has conducted an analysis of farmers’ perceptions and acceptance of the use of desalinated seawater for irrigation. The study is based on collected data from a survey completed by farmers in southeastern Spain who do not use desalinated seawater. The main results indicate that desalinated seawater as a water supply source has the lowest acceptance level for farmers. Barriers for its use are price, the need for additional fertilization, and the perception that it would negatively affect the yield and crop quality. The farmers’ general level of knowledge about the impact of using desalinated seawater in agriculture is extremely low. Furthermore, farmers consider it a priority that their startup investment should be subsidized and that water prices should be reduced. Based on the study findings, this paper makes recommendations for the decision-making process in order to improve farmers’ acceptance levels

In situ decolorization monitoring of textile dyes for an optimized UV-LED/TiO2 reactor

Heterogeneous photocatalysis, using photocatalysts in suspension to eliminate diverse contaminants, including textile wastewater, has several advantages. Nevertheless, current absorbance and decolorization measurements imply sample acquisition by extraction at a fixed rate with consequent photocatalyst removal. This study presents online monitoring for the decolorization of six azo dyes, Orange PX-2R (OP2), Remazol Black B133 (RB), Procion Crimson H-EXL (PC), Procion Navy H-EXL (PN), Procion Blue H-EXL (PB), and Procion Yellow H-EXL (PY), analyzing the spectrum measured in situ by using the light scattering provided by the photocatalyst in suspension. The results obtained have corroborated the feasibility of obtaining absorbance and decolorization measurements, avoiding disturbances in the process due to a decrease in the volume in the reactor.Peer ReviewedPostprint (published version

Improving scope sensitivity in contingent valuation: joint and separate evaluation of health states

We present data of a contingent valuation survey, testing the effect of evaluation mode on the monetary valuation of preventing road accidents. Half of the interviewees was asked to state their willingness to pay (WTP) to reduce the risk of having only 1 type of injury (separate evaluation, SE), and the other half of the sample was asked to state their WTP for 4 types of injuries evaluated simultaneously (joint evaluation, JE). In the SE group, we observed lack of sensitivity to scope while in the JE group WTP increased with the severity of the injury prevented. However, WTP values in this group were subject to context effects. Our results suggest that the traditional explanation of the disparity between SE and JE, namely, the so-called “evaluability,” does not apply here. The paper presents new explanations based on the role of preference imprecision

La tesis del perro-guardián: revisión de una teoría clásica.

Sin resume

Eficiencia energética: un problema, una reflexión y una solución

Peer Reviewe