Resumen de Aportaciones al proyecto, construcción y reparación de pavimentos de hormigón
The construction and conservation of road networks represent a major part of public expenditure. For instance, the EU-28 countries annually spend approximately EUR 20.000 million on roadway preservation. These figures highlight the need to develop more efficient methods for the design, construction and maintenance of pavements. Concrete pavements, including both new construction and strengthening (whitetoppings and overlays), offer many advantages over bituminous ones. These advantages provide more cost-effective and environmentally sustainable solutions. This is because their longer lifetime, lower cost at the long term, the capacity to reduce fuel consumption, etc.
Nevertheless, some countries such as Spain have no tradition in the use of concrete as a road construction material. This is confirmed by the fact that more than 99% of the roads belonging to the “Red de Carreteras del Estado” (National Highway Network) are asphalt roads. Consequently, technicians are not committed to implement the use of concrete and asphalt pavements tend to be perpetually applied. The limited application of concrete pavements at the state level might be explained due to limitations in pavement-design software and the low availability of specialized machinery, among other causes. Furthermore, whitetoppings and overlays present inherent uncertainties related to the interfacial bond strength that may have a negative effect on the structural performance and make its use even more difficult.
This doctoral thesis addresses these aspects with the global objective of facilitating the use of concrete in both newly constructed pavements and road preservation. To this end, a cross-sectional study work has been conducted, involving the development of a new pavement calculation software, an experimental program and the construction of four real-scale pavements.
The software allows the design and checking of multilayer pavements adopting different calculation methodologies depending on the structural typology and also considering interfacial debonding due to environmental effects. Likewise, the experimental program analyses the use of Self-Compacting High-Performance Concrete to optimize the adhesive strength in whitetoppings and overlays.
On the other hand, the use of shear connectors to improve the post-cracking interfacial strength has been investigated by means of real-scale pavements. A simplified theoretical framework to design the connector distribution is also provided. In the same way, two Roller-Compacted Concrete built with asphalt pavers have been evaluated, providing some recommendations for the use of this construction technique. The findings of this doctoral thesis are an additional and necessary step to spread the construction of concrete pavements, particularly in Spain.
