Revista 28
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Ítem Road accident analysis(2014-09-30 00:00:00) Ávila González, BernaldThe handling and care of a traffic incident better known as "traffic accident” is a process which can be seen in a number of positions and in which the elements involved in the accident are in succession, until it produces result. The problem of the high incidence of mortality from land traffic accidents in the world is a huge concern, this results and responsibilities arising from this type of critical accidents. We cannot let the issue be handled statistically as being so sadly transcendental order in the world. The custom has led us to understand that the problem of traffic accidents is exclusively by public safety, because in them, the police intervene directly, either to prevent, to mediate, or to protect the scene which there are injured or killed. Although many countries are taking important steps to increase road safety, much remains to be done to halt or reverse the increasing trend in the number of fatalities due to traffic accidents.Ítem Stochastic analysis of continuously reinforced concrete pavements(2014-09-30 10:22:22) Leiva Villacorta, Fabricio; Vargas Nordcbeck, AdrianaContinuously reinforced concrete pavements are rigid pavements that are reinforced with steel bars in the longitudinal direction and are built without transverse joints. In this type of pavements it is important to control crack spacing and width, as well as the stress level in the steel bars so that these parameters remain within a range that will ensure good pavement performance.Considering variability of material properties and slab thickness through a stochastic analysis may help optimize the design process and reduce uncertainty. The objectives of this study were to evaluate the design methodology for continuously reinforced concrete pavements using a probabilistic analysis and to evaluate the variability of the design parameters: crack spacing, crack width and steel stress. To accomplish these objectives, the variability of the material properties and slab thickness was included through the Monte Carlo simulation method for a case study.Ítem Proposal for municipalities and local governments pavement management systems(2014-09-30 10:21:20) Sotil Chávez, AndrésThe following paper provides a proposal for a Pavement Management System for municipalities and/or local government with low funds, and from which a further sophistication can take place.The paper has the main objective of proposing to the respective jurisdictions a methodology that allows abandon the maintenance practices based on politics (local pressures, claims), to convert it into a more objective, rationalized and programmed probabilistic/stochastic methodology, based on serviceability and functional evaluations.Once the PMS is established, it is proposed that the jurisdictions start building a historic database so that they can jump towards an empiric methodology of their own, that eventually will allow the future implementation of mechanistic-empiric methodologies.This paper provides an applicative example that can be used as an example by other jurisdictions. Even more, it can be taken as the starting point for the preparation and later implementation of a national manual for the country’s PMS.Ítem Emulsion primers, their contribution to bonding(2014-09-30 10:23:05) González Sburlati, Rubén Osmar; Sapei, JoséAsphalt irrigation in its various types, performs specific functions in the structure of a road during the construction phase or their service life. In particular, the so-called "Irrigation Primer " is used in underlying layers, in order to generate a transition surface with the new asphalt layer; thus the tack or prime coat will be placed on a surface to ensure a good bond with the overlying layer. For a long time Diluted Asphalts (Cut Back mediums) where used, but have been discontinued for environmental and economic reasons. Asphalt emulsions are replacing diluted asphalts with very good performance. The advances on emulsifiers technology and facilities producing more “specialties”, have allowed to design and characterize a special emulsion for Irrigation Primer. The Standard Reference is the IRAM 6691 - Asphalts - Conventional cationic asphalt emulsions - Classification and requirements. This paper evaluates the penetration capabilities of Asphalt Emulsions according to the described standard reference, considering new primers that are capable of generating the required transfer surface for any base.Ítem Comparative characterization of aggregates obtained from igneous rocks used in road construction(2014-09-30 10:02:23) Chiman, Alexei; Chiman, Larissa; Sanabria Grajales, Luis Enrique; Correa Avello, Jhon WilsonThe performance of mineral aggregates in road construction asphalt mixtures, specifically depends on a complex interaction of factors including geological component (rock type, and general mineralogical variation of mineral material) will be reflected in the physical and mechanical properties for use, such as mechanical strength, durability and performance, among others.The analysis of aggregates, mostly focus on the evaluation and correlation of physical properties that define their competition and shown little interest in improving the prediction of the integral behavior of mineral material.In this sense, as a contribution to get an estimate on comparative characterization of aggregates then assessing some geological and mechanical aggregate properties from igneous rocks, and correlations among themselves and with some particular mineralogical characteristics is presented.