Functionality, effectiveness of the asphalt reinforcement grid made of polyester and requirements of the construction sites bases on project examples in Africa
The demand for increased mobility on the African continent has been steadily growing over the years. The heavy traffic loads plays a considerable role on the lifetime of road pavements. Influenced by the interests of increasing economic development of a region / country has resulted in significantly increased traffic volumes. This growth is noticeable not only in urban, but also in rural areas. New regions have been developed and/or have gained in economic importance, which adds additional stress to the existing road network. In addition to the higher dynamic loads, climatic influences also play an important role and contribute to the formation of cracks and deformations in the existing roads. Despite the financial constraints, the existing road network must be gradually adapted to these new increased loads and associated stresses. The maintenance/rehabilitation of the existing road network is of central importance for the extension of the usability and service life of asphalt and concrete roads.
For over more than 40 years, the use of appropriate asphalt reinforcement geogrids manufactured form polyester, has been one of the most beneficial options for the rehabilitation of existing roads. This article provides an overview of the requirements, the functionality and the effectiveness of the asphalt reinforcement to delay and partially prevent the propagation of reflective cracks, as well as the extension of the maintenance intervals and the associated cost savings over the period of use, not to mention increased sustainability. This paper includes practical examples of construction projects in Africa and the important requirements for the correct installation of the asphalt reinforcement.
Reflective cracking can occur, easily and rapidly, in cracked pavements rehabilitated using a simple asphalt overlay. In order to delay the development of reflective cracking, an asphalt reinforcement grid can be placed before the new asphalt wearing course. When choosing the suitable product for a particular pavement rehabilitation, construction conditions and material characteristics must be taken into consideration.
The presented laboratory results, as well as case studies have shown that the use of a polyester polymer asphalt reinforcing grid in pavement rehabilitation can offer significant advantages. Based on the observed performance, it is possible to conclude that asphalt reinforcement is an effective treatment against reflective cracking in asphalt overlays, resulting in an extension of the service life of a rehabilitated pavement and reduced the maintenance costs.