Evaluate the inclusion of micro polymers and portland cement as a soil stabilizing agent for the formation of rasants

16 páginas : fotos, imágenes.La estabilización de suelos se basa en la aplicación de un agente químico que permite mejorar las propiedades físicas y mecánicas del suelo a tratar, dentro de estas se encuentran la capacidad portante y la resistencia a la compresión. Un agente de este tipo debe ser utilizado de acuerdo con las especificaciones técnicas existentes o las consideraciones expuestas por el fabricante del producto. Este tipo de tratamiento es realizado en suelos con propiedades desfavorables y que presentan condiciones de inestabilidad volumétrica, alto contenido de humedad y baja capacidad de soporte. En la actualidad existen métodos de estabilización como el uso de cal, cemento portland, bitúmenes y productos químicos que buscan controlar esas deficiencias. En efecto, el presente artículo busca analizar el uso combinado de micro polímeros y de cemento hidráulico para el mejoramiento del suelo que va ser utilizado como capa rasante en la conformación de una vía de acceso para una locación petrolera, esto se hace a partir de los resultados que arrojan las pruebas de laboratorio en las que se conocen las características del suelo en su estado natural y para determinar cuál es el mejoramiento de sus propiedades a partir de la inclusión del agente estabilizador con el fin de evaluar una alternativa diferente de estabilización a las conocidas bajo los procedimientos normados por el Instituto Nacional de Vías - INVIAS para tratamientos de este tipo en el suelo.Soil stabilization is based on the application of a chemical agent that improves the physical and mechanical properties of the soil to be treated, they are inside the bearing capacity and resistance to compression. An agent of this type must be used in accordance with the existing technical specifications or the considerations set out by the manufacturer of the product. This type of treatment is performed on soils with unfavorable properties and present conditions of volume instability, high moisture content and low bearing capacity. Currently, there are methods of stabilization as the use of lime, portland cement, bitumen and chemicals that seek to control these deficiencies. Indeed, this article will analyze the combined use of micro polymer and hydraulic cement for the improvement of the soil that will be used as flush layer in the formation of an access road to an oil lease, this is done from of the results that shed the lab tests in which the characteristics of the soil are known, in its natural state and to determine what is the improvement of its properties from the inclusion of the stabilizing agent in order to evaluate an alternative different stabilization to the known under procedures regulated by the National Institute of Pathways - INVIAS for treatments of this type on the ground

Molecular dynamics simulations of complex shaped particles using Minkowski operators

The Minkowski operators (addition and substraction of sets in vectorial spaces) has been extensively used for Computer Graphics and Image Processing to represent complex shapes. Here we propose to apply those mathematical concepts to extend the Molecular Dynamics (MD) Methods for simulations with complex-shaped particles. A new concept of Voronoi-Minkowski diagrams is introduced to generate random packings of complex-shaped particles with tunable particle roundness. By extending the classical concept of Verlet list we achieve numerical efficiencies that do not grow quadratically with the body number of sides. Simulations of dissipative granular materials under shear demonstrate that the method complies with the first law of thermodynamics for energy balance.Comment: Submitted to Phys. Rev.

Foreign Language Learning in Early Grades: Teaching Strategies for Classroom Instruction

Esta monografía analiza los procesos de aprendizaje de una lengua extranjera en primer grado de primaria: estrategias didácticas para la enseñanza en el aula a partir de una revisión de la literatura relacionada con este tema. Se busca contextualizar al lector sobre la naturaleza de las estrategias didácticas utilizadas en el aula por los docentes, tomando como fuente algunos documentos, artículos con resultados científicos, teorías e investigaciones afines a este tema. Teniendo en cuenta los aspectos anteriores, el objetivo a alcanzar, a partir de los fundamentos teóricos y prácticos, y la interpretación hermenéutica realizada en los diferentes textos, es proponer unas pautas encaminadas a fortalecer los métodos que deben utilizarse para un mejor aprendizaje de los niños que cursan primer grado de primaria las cuales debe enfocarse en tres situaciones específicas que se refieren a estrategias de enseñanza, actividades de aula y construcción metodológica.This monograph analyses the processes of learning a foreign language in the first grade of elementary school: didactic strategies for teaching in the classroom based on a bibliographic review. It seeks to contextualize the reader on the nature of the didactic strategies used in the classroom by teachers, taking as a target population documents, articles with scientific results, theories, and research related to the subject. Taking into account the above aspects, the objective to be achieved based on the theoretical and practical foundations is to propose some guidelines aimed at strengthening the methods that should be used for better learning in children in the first-grade of school, which should focus on three specific situations that refer to teaching strategies, classroom activities, and methodological construction

Model-driven Enterprise Systems Configuration

Enterprise Systems potentially lead to significant efficiency gains but require a well-conducted configuration process. A promising idea to manage and simplify the configuration process is based on the premise of using reference models for this task. Our paper continues along this idea and delivers a two-fold contribution: first, we present a generic process for the task of model-driven Enterprise Systems configuration including the steps of (a) Specification of configurable reference models, (b) Configuration of configurable reference models, (c) Transformation of configured reference models to regular build time models, (d) Deployment of the generated build time models, (e) Controlling of implementation models to provide input to the configuration, and (f) Consolidation of implementation models to provide input to reference model specification. We discuss inputs and outputs as well as the involvement of different roles and validation mechanisms. Second, we present an instantiation case of this generic process for Enterprise Systems configuration based on Configurable EPCs

Simulation of the hydraulic fracture process in two dimensions using a discrete element method

We introduce a discrete element simulation for the hydraulic fracture process in a petroleum well which takes into account the elastic behavior of the rock and the Mohr-Coulomb fracture criterium. The rock is modeled as an array of Voronoi polygons joined by elastic beams, which are submitted to tectonical stresses and the hydrostatic pressure of the fracturing fluid. The fluid pressure is treated like that of a hydraulic column. The simulation reproduces well the time and dimensions of real fracture processes. We also include an analysis of the fracturing fluid loss due to the permeability of the rock which is useful in an efficiency analysis of the treatment. The model is a first step for future applications in the petroleum industry

Effect of frictional heat dissipation on the loss of soil strength

In the present paper through a shear test on a fully saturated granular medium, simulated by the discrete element method, the effect of the heat produced by friction on the internal pore water pressure is explored. It is found that the dissipated energy is enough to increase the pore pressure and reduce the soil strength. In adiabatic and impermeable conditions the heat builds up quickly inside the shear band, and the softening is more pronounced. It is found as well that for real geological materials, heat conduction is not enough to reduce the pore pressure, and the softening prevails. Nevertheless, it is observed that the hydraulic conduction may mitigate or completely eliminate the temperature growth inside the shear band. This result provides new understanding on the thermodynamic factors involved in the onset of catastrophic landslides

Lucha y plan anti-contrabando de la DIAN en Colombia

El transporte y la logística internacional son muy importantes para una empresa que accede a los mercados internacionales, pues inicia con la llegada del pedido del exterior y finaliza con la entrega del producto al cliente. En estos casos se determina varios factores como son: el medio de transporte, la documentación; el embalaje, los seguros, los cuales se tienen en cuenta para los costos y el servicio que se le otorgue al cliente. Dependiendo de este costo es que se facilita una adecuada gestión logística y donde se reducen retrasos en el despacho de aduanas, perdidas de mercancía por falta de seguro y se maximiza la recaudación de ingresos aduaneros. Es allí donde nace el apoyo de la Dirección de Impuestos y Aduanas Nacionales porque son los que controlan y administran el paso de los productos para gravarlos con los impuestos correspondientes al país donde se importan, equilibrando su valor de mercado y reduciendo la competencia desleal; facilitando las operaciones de comercio exterior con el fin de garantizar la sostenibilidad del Estado Colombiano, acelerando las transacciones y mejorando la conformidad con los requisitos legales que rigen el comercio internacional. La Dian ha considerado que la lucha contra el contrabando es un prioridad para la economía colombiana, por ello propuso la ley Anti-contrabando y la formulación de una plan-anticontrabando, enfrentando de esta manera la competencia desleal realizadas por personas y organizaciones con acciones ilegales como lavados de activos, evasión fiscal, contrabando y poder sancionarlos con las autoridades competentes