Selección de forjados unidireccionales con criterios técnicos, económicos y sostenibles

This paper presents a method for finding the optimal floor slabs according to the requirements of the Spanish Building Code (CTE), the Spanish Structural Concrete Code (EHE-08) and good building practices. This method is applied to the case of one-way floor slabs with on-site cast ribs according with the characteristics and performance parameters usually offered by firms in the industry. The initial data and the variables involved in the process cover the technical viability, sustainability and monetary cost of slabs by incorporating specific ratios to assess the suitability of each solution. The method set out here may prove helpful to construction specialists who need to select optimal-cost floor slabs with the lowest environmental impacts.En este artículo se presenta un método para la búsqueda de forjados óptimos tomando en cuenta las exigencias del Código Técnico de la Edificación, CTE, de la Instrucción de Hormigón Estructural, EHE-08, y de la buena práctica constructiva. Esta metodología se aplica al caso de forjados unidireccionales con nervio hormigonado in situ de acuerdo a las características y prestaciones habituales que ofertan las empresas del sector. Los datos de partida y las variables implicadas en el proceso hacen referencia a la viabilidad técnica, sostenibilidad y coste económico de los forjados a través de la incorporación de ratios específicos que evalúan la idoneidad de cada solución. El método aquí expuesto pretende servir de ayuda para el profesional de la construcción que necesite seleccionar aquellos forjados de coste óptimo que proporcionen el menor impacto medioambiental

Selección de forjados unidireccionales con criterios técnicos, económicos y sostenibles

This paper presents a method for finding the optimal floor slabs according to the requirements of the Spanish Building Code (CTE), the Spanish Structural Concrete Code (EHE-08) and good building practices. This method is applied to the case of one-way floor slabs with on-site cast ribs according with the characteristics and performance parameters usually offered by firms in the industry. The initial data and the variables involved in the process cover the technical viability, sustainability and monetary cost of slabs by incorporating specific ratios to assess the suitability of each solution. The method set out here may prove helpful to construction specialists who need to select optimal-cost floor slabs with the lowest environmental impacts.<br><br>En este artículo se presenta un método para la búsqueda de forjados óptimos tomando en cuenta las exigencias del Código Técnico de la Edificación, CTE, de la Instrucción de Hormigón Estructural, EHE-08, y de la buena práctica constructiva. Esta metodología se aplica al caso de forjados unidireccionales con nervio hormigonado <i>in situ</i> de acuerdo a las características y prestaciones habituales que ofertan las empresas del sector. Los datos de partida y las variables implicadas en el proceso hacen referencia a la viabilidad técnica, sostenibilidad y coste económico de los forjados a través de la incorporación de ratios específicos que evalúan la idoneidad de cada solución. El método aquí expuesto pretende servir de ayuda para el profesional de la construcción que necesite seleccionar aquellos forjados de coste óptimo que proporcionen el menor impacto medioambiental

The granite and glacial landscapes of the Peneda-Gerês National Park

Granite and glacial landforms are presented as the main geomorphological landscape features of the Peneda-Gerês National Park. The park was established in 1971 and it is the only national park and most important protected area in Portugal. The aesthetic attractiveness is supported mainly by the distinct granite landscape of the Gerês and Peneda Mountains, where the post-orogenic Variscan Gerês gran- ite facies occurs. The rugged relief is poorly covered by vegetation, differentiating it from the surrounding moun- tainous areas and the most distinctive landforms are bornhardts, locally named as “medas”. Typical glacial landforms, such as U-shaped valleys, cirques and moraines, express the sheltered character of a low-altitude glaciation, which is of great significance in the context of the Pleistocene glaciation in Southern Europe.This work is co-funded by the European Union through the European Regional Development Fund, based on COMPETE 2020 (Programa Operacional da Competitividade e Inter nacionalização), project ICT (UID/GEO/04683/2013) with reference POCI-01-0145- FEDER-007690 and Portuguese national funds pro vided by Fundação para a Ciência e Tecnologi

Periglacial environments and frozen ground in the central Pyrenean high mountain area: Ground thermal regime and distribution of landforms and processes

Producción CientíficaThe periglacial belt is located in the highest parts of temperate mountains. The balance between mean air and ground temperatures and the presence of water determine the effectiveness of periglacial processes related to permafrost, the active layer or seasonally frozen ground (SFG). This study combines thermal and geomorphological data obtained in four Pyrenean massifs (Infierno‐Argualas, Posets, Maladeta and Monte Perdido) to improve knowledge on the occurrence and distribution of frozen ground. The methodology used is based on the study of landforms as frozen ground indicators, mapping processes, ground temperature analysis, basal temperature of snow, thermal mapping and geomatic surveys on rock glaciers and protalus lobes. In the Pyrenean high mountain areas the lower limit of frozen ground is at ~2,650m a.s.l., possible permafrost appears above 2,650m a.s.l. on north‐ and south‐facing slopes, and probable permafrost is dominant above 2,900m a.s.l. Unfrozen ground with cold‐associated geomorphological processes reach 2,900m a.s.l. and unfrozen and frozen ground distribution points to a patchy pattern throughout the periglacial belt. The most widespread frozen grounds are SFG. The thermal data, mean annual ground temperature, cold season temperatures, bottom temperature snow measurements, freeze/thaw cycles and distribution of landforms permit the establishment of a periglacial land system divided into three main belts: infraperiglacial, middle periglacial and supraperiglacial. The large number of processes and landforms that are involved and their altitudinal and spatial organization make up a complex environment that determines the geoecological dynamics of high mountain areas.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (projects CGL2015-68144-R / GL2017- 82216-R

Pulsaciones glaciares y terrazas marinas escalonadas en los alrededores de la Base Antártica Española. Isla Livingston. Shetland del Sur

The recent fluctuations of the glaciers can be modellised near the Antartic Spanish Base (BAE), where six morainic arches are exposed, as well as eight marine terraces up to + 18. 6 m. Some conclusions about the recent evolution of the island can be drawn from the geomorphological maps and profiles elaborated

Sedimentología de la formación Miers Bluff en los alrededores de la Base Antártica española. Isla Livingston. Shetland del Sur

The Míers Bluff Formation crops out ín the Hurd Península, Livíngston Island. It consíst of greywackes and slates, organísed ín coarseníng-thíckeníng and fíníng-thínníng cycles. They have been ínterpreted as channellísed and non-channellísed turbídites from a míd- and outer turbídítíc fan

Major Pleistocene and Holocene glacial episodes in the Khumbu region, southern side of Mount Everest (Nepalese Himalaya)

Se amplía hacia la vertiente meridional del Everest la cartografía de la geomorfología glaciar realizada anteriormente por los autores en el sector tibetano de este macizo. Se distinguen cuatro fases glaciares principales desde e/ Pleistoceno a la Pequeña Edad de/ Hielo, con frentes morrénicos situados a las siguientes altitudes: 2.400 m, 4.330 m, 4.600 m, Y 4.926 m

Notas preliminares sobre la geomorfología glaciar del Valle de Rongbuk, vertiente norte del Qomolangma (Everest). Tíbet. R. P. China

Five major glacial episodes are diferenciated in Rongbuk Valley along the Upper Pleistocene and Holocene, till the Little Ice Age, with the frontal morraines at 5150, 5140, 5075, 4970 and 4.700 meters over sea leve