Impact of defective production of asphalt mixture resulting in damaged asphalt layers

摘要

In practice it often happens that a newly built road soon, after the asphalt mixture is added, starts showing first cracks and damages, which are not necessarily always a fault of the contractor, who built in the asphalt mixture, but can derive from the production of asphalt mixture. Such mistakes in the production of the asphalt mixture are hard to prove, since all the contractors usually put the blame on the automatic mixing production in the asphalt plant. During the production of the asphalt mixture, samples of input materials are taken, while the produced asphalt mixture is also sampled at the end of the production process. An inadequate asphalt mixture can be produced within the asphalt plant due to the damages in its machinery, inadequate input materials or the human factor plays a role in it, since we must not forget that all the machinery within the asphalt plant and computer programmes are supervised by man. Human factor also plays a role in the correct storing of input materials. It is the authority of the head of the asphalt plant to decide to ship the mixture to the contractor or not.ududThe Master's thesis researches the reasons for errors in the production which is completely automated since it is based on a computer programme. The current Slovene legislation on the production of asphalt mixtures and technical specification for roadways was analysed. The legislation defines in detail the input materials, parts of the asphalt plant, the production procedure and the enforcement of the control, and includes the contents of the procedural book of quality control in the asphalt plant. All the most common damages to asphalt roadways, which may be a result of errors in the asphalt mixture production and may derive from material deterioration, are given at the end of the Master's thesis. Material deterioration can be a result of inadequate storing of input materials, errors in measuring dosages, temperatures that are too low during the mixing process, the time of mixing and of numerous other reasons. ud