505 research outputs found
Field study of infiltration capacity reduction of porous mixture surfaces
Porous surfaces have been used all over the world in source control techniques to minimize flooding problems in car parks. Several studies highlighted the reduction in the infiltration capacity of porous mixture surfaces after several years of use. Therefore, it is necessary to design and develop a new methodology to quantify this reduction and to identify the hypothetical differences in permeability between zones within the same car park bay due to the influence of static loads in the parked vehicles. With this aim, nine different zones were selected in order to check this hypothesis (four points under the wheels of a standard vehicle and five points between wheels). This article presents the infiltration capacity reduction results, using the LCS permeameter, of Polymer-Modified Porous Concrete (9 bays) and Porous Asphalt (9 bays) surfaces in the University of Cantabria Campus parking area (Spain) 5 years after their construction. Statistical analysis methodology was proposed for assessing the results. Significant differences were observed in permeability and reduction in infiltration capacity in the case of porous concrete surfaces, while no differences were found for porous asphalt depending on the measurement zone
Water quality and quantity assessment of pervious pavements performance in experimental car park areas
Pervious pavements have become one of the most used sustainable urban drainage system (SUDS) techniques in car parks. This research paper presents the results of monitoring water quality from several experimental car park areas designed and constructed in Spain with bays made of interlocking concrete block pavement, porous asphalt, polymer-modified porous concrete and reinforced grass with plastic and concrete cells. Moreover, two different sub-base materials were used (limestone aggregates and basic oxygen furnace slag). This study therefore encompasses the majority of the materials used as permeable surfaces and sub-base layers all over the world. Effluent from the test bays was monitored for dissolved oxygen, pH, electric conductivity, total suspended solids, turbidity and total petroleum hydrocarbons in order to analyze the behaviour shown by each combination of surface and sub-base materials. In addition, permeability tests were undertaken in all car parks using the ‘Laboratorio Caminos Santander’ permeameter and the Cantabrian Portable Infiltrometer. All results are presented together with the influence of surface and sub-base materials on water quality indicators using bivariate correlation statistical analysis at a confidence level of 95%. The polymer-modified porous concrete surface course in combination with limestone aggregate sub-base presented the best performance
Proyecto: una exploración del proceso creativo audiovisual
‘Proyecto’ es un cortometraje de ficción que recoge las experiencias propias de las realizadoras, con
el fin de reflexionar sobre el proceso creativo y las inseguridades que a partir de él surgen. Es así
que, ‘Proyecto’ se crea bajo la premisa de adentrarnos en los pensamientos de una persona,
explorando cercana y empáticamente el sentimiento de incapacidad y desconfianza hacia las
habilidades propias, ya sea a través de situaciones metafóricas, de diálogos misteriosos, o de
metraje propio que revela nostálgicamente la vida de nuestro personaje. En el presente trabajo de
investigación, se detalla el proceso de este proyecto audiovisual, desde sus inicios y la concepción
de la idea, hasta el proceso de realización en cuanto a los diversos ámbitos de lo audiovisual,
teniendo en cuenta el contexto en el que el proyecto fue realizado Si bien este es un cortometraje de
ficción, no es tal cual una ficción pura y dura, pero mezcla diversos recursos narrativos que se
consideraron pertinentes para transmitir nuestro mensaje. De esta manera, buscamos se logre en el
espectador una reflexión sobre cómo nos acercamos a cada proyecto o idea que emprendemos,
desde el ejemplo propio de nuestro personaje que crea este cortometraje, para lograr reconciliarnos
con nuestros propios pensamientos, ya sean negativos y oscuros, o fantasiosos y fuera de la
realidad.Proyecto' is a short fiction film that gathers the filmmakers' own experiences, in order to reflect on
the creative process and the insecurities that arise from it. Thus, 'Proyecto' is created under the
premise of entering into the thoughts of a person, exploring closely and empathetically the feeling
of incapability and distrust towards one's own abilities, either through metaphorical situations,
mysterious dialogues, or personal footage that nostalgically reveals the life of our character. In this
paper, we will detail the process of this audiovisual project, from its beginnings and the conception
of the idea, to the process of realization in terms of the various areas of the audiovisual, taking into
consideration the context in which the project was made. Although this is a short fiction film, it is
not a pure fiction, but it mixes various narrative resources that were considered relevant to convey
our message. In this way, we seek to achieve in the viewer a reflection on how we approach each
project or idea we undertake, from the example of our own character who creates this short film, to
achieve reconciliation with our own thoughts, whether negative and dark, or fanciful and out of
reality.Trabajo de investigació
Proposal of a New Porous Concrete Dosage Methodology for Pavements
Although porous concrete pavement design methods are mainly focused on maintaining high permeability rates in order to improve their ability to manage stormwater runoff, the mixture strength is paramount for its durability and service life. This paper proposes a new mixture design method for porous concrete, named PCD (porous concrete design), derived from the ACI 522R-10 and ACI 211.3R-02 standards. The aim is to improve mechanical strength in porous concrete mixtures, while ensuring enough permeability for its use in urban roads. With PCD methodology it is possible to obtain mechanical strengths 30% higher than those produced with ACI methodologies, while maintaining permeability rates close to 2 cm/s, lower than those obtained with ACI methods but still enough to manage extreme storm events. Finally, with the analytical Hierarchy Process (AHP) multi-criteria decision-making methodology and also bearing in mind safety variables, the best porous concrete mixtures are the ones produced with PCD methodology.This research was funded by the Spanish Ministry of Economy and Competitiveness and the European
Union (ERDF) through the project SUPRIS.SUReS (Ref. BIA2015-65240-C2-1-R)
Sustainable Drainage Practices in Spain, Specially Focused on Pervious Pavements
ABSTRACT. The Spanish climate is full of contrasts, with torrential rains and long droughts; under these conditions, appropriate water management is essential. In Spain, until the end of the twentieth century, water management and legislative development lagged behind other more developed countries. Nowadays, great efforts are being made to reverse this situation and improve both water management and legislation in order to control the two main problems related to stormwater management in cities: floods and diffuse pollution. In this context, Sustainable Urban Drainage Systems (SUDS) were developed as the main solution to these problems. The study of these techniques started in the 1970s in the USA, but they were not studied in Spain until 1993 when the University of Cantabria and CLABSA started to look into solutions for stormwater management. After 20 years of research and application, sustainable drainage in Spain is still behind other countries in spite of the efforts to change this situation, notably by the University of Cantabria with 10 years of experience in these techniques, mainly regarding pervious pavements, where more than 13 related research projects have been carried out. The future challenges focus on the application of pervious pavements for Urban Hydrological Rehabilitation
Study of the Raveling Resistance of Porous Asphalt Pavements Used in Sustainable Drainage Systems Affected by Hydrocarbon Spills
Permeable pavements are one of the most commonly-used sustainable drainage systems (SuDS) in urban areas for managing stormwater runoff problems. Porous asphalt is widely used in surface layers of permeable pavement systems, where it can suffer from accidental oil spills from vehicles. Oil spills affect bituminous mixes through the solvent action of the hydrocarbons on the bitumen, reducing the raveling resistance of asphalt pavements. In order to assess the raveling resistance in porous asphalt pavements, the Cantabro abrasion test was performed on 200 test samples after applying controlled oil spills. Three different types of binders were used: conventional bitumen, polymer-modified bitumen and special fuel-resistant bitumen. After analyzing the results, it was concluded that the most suitable bitumen to protect against oil leakages is the polymer-modified one, which is far better than the other two types of bitumen tested
All-Sky Near Infrared Space Astrometry
Gaia is currently revolutionizing modern astronomy. However, much of the
Galactic plane, center and the spiral arm regions are obscured by interstellar
extinction, rendering them inaccessible because Gaia is an optical instrument.
An all-sky near infrared (NIR) space observatory operating in the optical NIR,
separated in time from the original Gaia would provide microarcsecond NIR
astrometry and millimag photometry to penetrate obscured regions unraveling the
internal dynamics of the Galaxy.Comment: 7 page
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