Mauricio Pradena

Ride quality stability of jointed plain-concrete road pavements with short slabs

Curling and warping of jointed plain-concrete road pavements are not only unfavourable from the structural point of view but also from a functional perspective because road users can perceive different ride qualities during the day due to changes in slab curvature. The use of short slabs, an innovation of traditional jointed plain-concrete pavements, allows a reduction in concrete thickness due to traffic load configurations and also a reduction in curling and warping. The objective of this study was to compare the stability of ride quality in traditional and short-slab pavements. Using a walking profiler, precise international roughness index (IRI) measurements were taken every 10 m on both types of pavements in Chile at different times of the day and over two slab tracks. Roughness measurements using a high-speed laser profilometer over 12 km of additional short slabs in Chile were also considered. Changes in IRI of up to 0·6 m/km were obtained on traditional pavements. In contrast, the results clearly ...

Influence of early-age concrete behaviour on concrete pavements performance

Pukotine u razdjelnicama posljedica su ponašanja betona u početku uporabe konstrukcije što može utjecati na konstrukcijska svojstva betonskih kolnika. U radu se analiziraju dosadašnja znanja za procjenu utjecaja betona u početnom periodu uporabe betonske kolničke konstrukcije. Ispitivanje je pokazalo da je pri modeliranju ponašanja pukotina potrebno uzeti u obzir međudjelovanje (u vremenu i prostoru) grupe razdjelnica. Kao rezultat takvog pristupa može se predvidjeti odnos razdjelnica i širina pukotina kako bi se procijenili njihovi učinci na svojstva betonskih kolnika.Cracks in joints are the consequence of concrete behaviour in the initial period of use of pavement structures, which can affect structural properties of concrete pavements. Current knowledge on the influence of concrete in the initial period of use of concrete pavement structures is analysed in the paper. The analysis has shown that interaction (in space and time) of the group of joints must be taken into account in the scope of crack behaviour modelling. As a result of this approach, the relationship between joints and crack width can be predicted in order to evaluate their effects on properties of concrete pavements.

Utjecaj ponašanja svježeg betona na svojstva betonskih kolnika

Pukotine u razdjelnicama posljedica su ponašanja betona u početku uporabe konstrukcije što može utjecati na konstrukcijska svojstva betonskih kolnika. U radu se analiziraju dosadašnja znanja za procjenu utjecaja betona u početnom periodu uporabe betonske kolničke konstrukcije. Ispitivanje je pokazalo da je pri modeliranju ponašanja pukotina potrebno uzeti u obzir međudjelovanje (u vremenu i prostoru) grupe razdjelnica. Kao rezultat takvog pristupa može se predvidjeti odnos razdjelnica i širina pukotina kako bi se procijenili njihovi učinci na svojstva betonskih kolnika.Cracks in joints are the consequence of concrete behaviour in the initial period of use of pavement structures, which can affect structural properties of concrete pavements. Current knowledge on the influence of concrete in the initial period of use of concrete pavement structures is analysed in the paper. The analysis has shown that interaction (in space and time) of the group of joints must be taken into account in the scope of crack behaviour modelling. As a result of this approach, the relationship between joints and crack width can be predicted in order to evaluate their effects on properties of concrete pavements.

Aplicaciones de la administración integral de proyectos en la industria de la construcción: Segunda parte, proyectos viales

Este articulo constituye el tercero de una serie sobre la Administracion Integral de Proyectos (AIP) en la industria de la construccion en Chile, aun cuando muchos de los conceptos aqui vertidos son extrapolables a la realidad de otros paises y de otros sectores productivos. La base de la propuesta de la AIP en el mercado de la construccion fue presentada por los autores en un numero anterior de esta revista, y en el presente articulo se exhiben aspectos importantes de la aplicacion de la AIP al caso de proyectos viales, en particular caminos y carreteras. De esta manera, se revisa primeramente la necesidad de analisis profundos en este tipo de proyectos, debido a las altas inversiones que ellos significan, tambien se presentan las particularidades de los proyectos viales y el rol de la AIP en este tipo de proyectos. Posteriormente, se trata la importancia de la conservacion de los caminos y la necesidad de modelacion, para finalmente exponer las aplicaciones de la AIP tanto en proyectos publicos como privados. De acuerdo a lo presentado, se concluye que las herramientas que proporciona la Administracion Integral de Proyectos son necesarias y aplicables para el adecuado desarrollo de proyectos de caminos. Palabras clave: Administracion Integral de Proyectos, carreteras, caminos.