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Fliegl innovations concerning asphalt construction

MÜHLDORF / GERMANY, May 27, 2013 - Asphalt construction is a science in itself. However scientific research is rarely carried out on it. A mutual investigation by the Cologne Laboratory for construction machines (KLB) together with the Technical University of Darmstadt has changed all this.

The core results of the study show that the Fliegl push-off trailer “Asphaltprofi-Thermo” is capable of drastically improving the paving quality of asphalt. Dumpers with troughs made from steel or aluminum trail far behind.

An asphalt layer is only stable and durable when it has the lowest possible number of cavities. It can only have the lowest possible number of cavities, when it has been optimally compacted. It can only be optimally compacted when it is hot enough. The temperature of the mixture is the decisive factor in asphalt quality.

"Asphalt Thermo" during his work

Stable Asphalt layer made by Fliegl push-off trailer "Asphaltprofi Thermo". | photo: Fliegl


According to regulation (ZTV Asphalt-StB 07) the temperature of the mixture should not be less than 150°C It must be evenly hot and not have any cold nests in corners and angles, only then does the material and the binding agent have the optimal properties. In practice however, things are different. Tests from the KLB and TU Darmstadt show the dumpers with steel troughs do not keep the mixture hot enough. Thermal imaging cameras show that large amounts of heat are lost to the trough. The aluminum trough performs only marginally better. In particular during unloading large amounts of cold mixture are transferred into the paver. Even with covered dumpers the temperature can be as low as 100°C to 130°C. It takes at least one to two minutes, from the docking of the dumper until the initial mixture falls into the paver – the consequences of this are, the paver is not working and the mixture cools down. Both of these cause considerable loss of quality.

Fliegl's push-off trailer “Asphaltprofi-Thermo” delivers completely different results. Its side walls are fitted with 70 mm thick, highly insulated damp resistant insulating material. The effect: The thermal loss during transport is minimized, the temperature of the mixture in the trough never falls under 162°C and is so considerably over the required 150°C. It is during the transfer of the mixture to the paver that the advantages of the push-off technology really come to the fore. After the docking the “bit by bit” transfer of the mixture begins immediately with very high thermal stability in the paver.

The Fliegl ASW achieves a thermal stability that other transport systems do not even come close to. Its push-off technology is ideally suited for feeding an asphalt paver. It works straight away and guarantees a perfect mixture and homogeneity of the asphalt. The results: The required minimum degree of compaction of 98 % is easily achievable in practice. Achieving this optimal compacting is very important: At first it secures the stability of the later asphalt; secondly only it can fulfill the requirements of the current ZTV asphalt. For the construction company carrying out the work the Fliegl “Asphaltprofi-Thermo” brings security. It delivers the mixture so hot and homogeneous that the required degree of compaction is achieved without a problem. In this way they avoid huge contractual penalties or deductions from failing to attain the required installation quality. With all these advantages the Fliegl “ASW Asphaltprofi-Thermo” does not just improve asphalt construction, it revolutionizes it.

Although the Fliegl “Asphaltprofi-Thermo” was perfected for asphalt construction, it can show its strengths in other forms of construction work. It masters earth excavation and road construction, where normal dumpers fail – e.g. in tree lined avenues, in town centers with overhead electrical lines, under bridges and underground. The fact that the Fliegl “Asphaltprofi-Thermo” can be used throughout the year increases its efficiency and profitability and makes it an ideal longterm construction vehicle.