Cálculo del asiento elástico tridimensional de cimentaciones de rigidez variable en terrenos con una capa rígida inclinada

Las fórmulas basadas en la teoría de la elasticidad son ampliamente utilizadas para el cálculo de asientos de cimentaciones, ya que la totalidad de la normativa geotécnica recomienda su empleo. No obstante, estos métodos no cubren todas las situaciones geotécnicamente posibles ya que frecuentemente las condiciones geológicas son complejas. En este trabajo se analiza la influencia de la presencia de una capa rígida inclinada en los asientos elásticos de una cimentación superficial. Para ello se han resuelto 273 modelos tridimensionales no lineales de elementos finitos, variando los parámetros clave del problema: la inclinación y la profundidad de la capa rígida y la rigidez de la cimentación. Finalmente, se ha realizado un análisis estadístico de los resultados de los modelos y se ha propuesto una fórmula que puede ser utilizada en el cálculo de asientos por métodos elásticos, para tener en consideración la presencia de una capa rígida inclinada en profundidad.

A simple method to predict elastic settlements in foundations resting on two soils of differing deformability

This paper shows the analysis results obtained from more than 200 finite element method (FEM) models used to calculate the settlement of a foundation resting on two soils of differing deformability. The analysis considers such different parameters as the foundation geometry, the percentage of each soil in contact with the foundation base and the ratio of the soils’ elastic moduli. From the described analysis, it is concluded that the maximum settlement of the foundation, calculated by assuming that the foundation is completely resting on the most deformable soil, can be correlated with the settlement calculated by FEM models through a correction coefficient named “settlement reduction factor” (α). As a consequence, a novel expression is proposed for calculating the real settlement of a foundation resting on two soils of different deformability with maximum errors lower than 1.57%, as demonstrated by the statistical analysis carried out. A guide for the application of the proposed simple method is also explained in the paper. Finally, the proposed methodology has been validated using settlement data from an instrumented foundation, indicating that this is a simple, reliable and quick method which allows the computation of the maximum elastic settlement of a raft foundation, evaluates its suitability and optimises its selection process.

Relationship between piezometric level and ground deformations measured by means of DInSAR in the Vega Media of the Segura River (Spain)

Differential SAR Interferometry (DInSAR) is a remote sensing method with the well demonstrated ability to monitor geological hazards like earthquakes, landslides and subsidence. Among all these hazards, subsidence involves the settlement of the ground surface affecting wide areas. Frequently, subsidence is induced by overexploitation of aquifers and constitutes a common problem that affects developed societies. The excessive pumping of underground water decreases the piezometric level in the subsoil and, as a consequence, increases the effective stresses with depth causing a consolidation of the soil column. This consolidation originates a settlement of ground surface that must be withstood by civil structures built on these areas. In this paper we make use of an advanced DInSAR approach - the Coherent Pixels Technique (CPT) [1] - to monitor subsidence induced by aquifer overexploitation in the Vega Media of the Segura River (SE Spain) from 1993 to the present. 28 ERS-1/2 scenes covering a time interval of about 10 years were used to study this phenomenon. The deformation map retrieved with CPT technique shows settlements of up to 80 mm at some points of the studied zone. These values agree with data obtained by means of borehole extensometers, but not with the distribution of damaged buildings, well points and basements, because the occurrence of damages also depends on the structural quality of the buildings and their foundations. The most interesting relationship observed is the one existing between piezometric changes, settlement evolution and local geology. Three main patterns of ground surface and piezometric level behaviour have been distinguished for the study zone during this period: 1) areas where deformation occurs while ground conditions remain altered (recent deformable sediments), 2) areas with no deformation (old and non-deformable materials), and 3) areas where ground deformation mimics piezometric level changes (expansive soils). The temporal relationship between deformation patterns and soil characteristics has been analysed in this work, showing a delay between them. Moreover, this technique has allowed the measurement of ground subsidence for a period (1993-1995) where no instrument information was available.

Legislation on violence against women: overview of key components

This study aimed to determine if legislation on violence against women (VAW) worldwide contains key components recommended by the Pan American Health Organization (PAHO) and the United Nations (UN) to help strengthen VAW prevention and provide better integrated victim protection, support, and care. A systematic search for VAW legislation using international legal databases and other electronic sources plus data from previous research identified 124 countries/territories with some type of VAW legislation. Full legal texts were found for legislation from 104 countries/territories. Those available in English, Portuguese, and Spanish were downloaded and compiled and the selection criteria applied (use of any of the common terms related to VAW, including intimate partner violence (IPV), and reference to at least two of six sectors (education, health, judicial system, mass media, police, and social services) with regard to VAW interventions (protection, support, and care). A final sample from 80 countries/territories was selected and analyzed for the presence of key components recommended by PAHO and the UN (reference to the term "violence against women" in the title; definitions of different types of VAW; identification of women as beneficiaries; and promotion of (reference to) the participation of multiple sectors in VAW interventions). Few countries/territories specifically identified women as the beneficiaries of their VAW legislation, including those that labeled their legislation "domestic violence" law ( n = 51), of which only two explicitly mentioned women as complainants/survivors. Only 28 countries/territories defined the main forms of VAW (economic, physical, psychological, and sexual) in their VAW legislation. Most highlighted the role of the judicial system, followed by that of social services and the police. Only 28 mentioned the health sector. Despite considerable efforts worldwide to strengthen VAW legislation, most VAW laws do not incorporate the key recommended components. Significant limitations were found in the legislative content, its application, and the extent to which it provided women with integrated protection, support, and care. In developing new VAW legislation, policymakers should consider the vital role of health services.

Science & art of body percussion: a review

The purpose of this paper is to provide a comprehensive review of Body Percussion from all areas, focusing on existing academic literature and the contribution of different authors. Existing ethnographic publications are reviewed, as are the links with traditional dances, musical pedagogy, neuroscientific aspects, handclapping songs, use in shows, the sound properties of body percussion and, most importantly, the main authors who have systematically structured and build the foundations of body percussion in a coherent manner and with new contributions.

Durability and compressive strength of blast furnace slag-based cement grout for special geotechnical applications

Special foundations, most prominently micropiles and soil anchors, are frequently used in construction today. In Spain, the grout for these special technical applications is generally prepared with portland cement, although the codes and standards in place stipulate only the minimum compressive strength required, with no mention of cement type. Those texts also establish a range of acceptable water:cement ratios. In the present study, durability and compressive strength in cement grout prepared with blast furnace slag cement at different w/c ratios are characterised and compared to the findings for a reference portland cement grout. The results show that slag grout exhibits greater durability than the portland cement material and complies with the compressive strength requirements laid down in the respective codes.

Linguistic Knowledge of Reality: A Metaphysical Impossibility?

Reality contains information (significant) that becomes significances in the mind of the observer. Language is the human instrument to understand reality. But is it possible to attain this reality? Is there an absolute reality, as certain philosophical schools tell us? The reality that we perceive, is it just a fragmented reality of which we are part? The work that the authors present is an attempt to address this question from an epistemological, linguistic and logical-mathematical point of view.

Quaternary ammonium-functionalized silica sorbents for the solid-phase extraction of aromatic amines under normal phase conditions

Quaternary ammonium-functionalized silica materials were synthesized and applied for solid-phase extraction (SPE) of aromatic amines, which are classified as priority pollutants by US Environmental Protection Agency. Hexamethylenetetramine used for silica surface modification for the first time was employed as SPE sorbent under normal phase conditions. Hexaminium-functionalized silica demonstrated excellent extraction efficiencies for o-toluidine, 4-ethylaniline and quinoline (recoveries 101–107%), while for N,N-dimethylaniline and N-isopropylaniline recoveries were from low to moderate (14–46%). In addition, the suitability of 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica as SPE sorbent was tested under normal phase conditions. The recoveries achieved for the five aromatic amines ranged from 89 to 99%. The stability of the sorbent was evaluated during and after 150 extractions. Coefficients of variation between 4.5 and 10.2% proved a high stability of the synthesized sorbent. Elution was carried out using acetonitrile in the case of hexaminium-functionalized silica and water for 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent. After the extraction the analytes were separated and detected by liquid chromatography ultraviolet detection (LC-UV). The retention mechanism of the materials was primarily based on polar hydrogen bonding and π–π interactions. Comparison made with activated silica proved the quaternary ammonium-functionalized materials to offer different selectivity and better extraction efficiencies for aromatic amines. Finally, 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent was successfully tested for the extraction of wastewater and soil samples.

Revealing the Face of Isis

This reply to Gash’s (Found Sci 2014) commentary on Nescolarde-Selva and Usó-Doménech (Found Sci 2014b) answers the questions raised and at the same time opens up new questions.

Semiotic Vision of Ideologies

A semiotic theory of systems derived from language would have the purpose of classifying all the systems of linguistic expression: philosophy, ideology, myth, poetry, art, as much as the dream, lapsus, and free association in a pluridimensional matrix that will interact with many diversified fields. In each one of these discourses it is necessary to consider a plurality of questions, the essence of which will only be comprehensible by the totality; it will be necessary to ask, in the first place, what will be the purpose of this language, what function does it fulfill and for which reason has it been constructed. The concept of World vision (WV) is introduced and its relation with Generalized Collective Conscience (GCC) and Particularized Collective Conscience. Culture implies a particular WV. Culture creates GCC. The semantic field is a structure that formalizes the units of a certain culture constituting a portion of the vision of the Reality that owns this culture. An ecological case is explained.

Theory of Systems, Systems Metaphysics and Neoplatonism

Science has been developed from the rational-empirical methods, having as a consequence, the representation of existing phenomena without understanding the root causes. The question which currently has is the sense of the being, and in a simplified way, one can say that the dogmatic religion lead to misinterpretations, the empirical sciences contain the exact rational representations of phenomena. Thus, Science has been able to get rid of the dogmatic religion. The project for the sciences of being looks to return to reality its essential foundations; under the plan of theory of systems necessarily involves a search for the meaning of Reality.