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Gewählte Master / Diploma Thesis:

Nikolaus Wieser (2015): Physikalische Modellierung zur Optimierung von flexiblen Murbarrieren am Beispiel Trattenbach.
Master / Diploma Thesis - Institut für Alpine Naturgefahren (IAN), BOKU-Universität für Bodenkultur, pp 110. UB BOKU obvsg

Data Source: ZID Abstracts
Abstract:
To protect the route (Salzburg-Wörgl) of the Austrian Federal Railway in the section of the „Trattenbach“ in the community of Taxenbach a new protection concept was developed. The project includes two protective structures, one against debris flow and one protective structure against bed load transport. This thesis deals with the optimization of the protective structure against debris flow. Due to the poor accessibility of the retention area a new type of protection structure has been developed. To test and optimize this type of barrier a small scale model of the channel with a scale of 1:30 was created in the laboratory of the institute of Mountain Risk Engineering. To guarantee the possibility of clearing out the retention area an open crown protection structure with a slit width of 4m as a basis unit was used. The continuous slit was closed by using an installation of a debris flow net. Altogether 21 tests were performed. In the laboratory occurring forces, surface pressures and anchor forces in the main cables have been measured. Based on this tests the measured pressures could be verified with the calculated pressures according to the ONR 24801 (2013) with an average deviation of 9,5%. Furthermore a prototype of the actual check dam with six supporting cables was exposed to the debris flow. In this connection the anchor forces of the ropes were observed. Due to the fact that the system is very stiff and has a high initial tension the suspension strand couldn’t deflect as it does in reality. That’s why during the tests very high anchor forces have been measured. However a comparison of the impacts with the norm could be verified with an average deviation of 10,5%.To optimize the basal opening three different opening heights were examined. By changing the opening heights a condition for the separation of the several structure functionalities could be identified. At a height over 1.8 * d90 a dosage effect of the structure could be assumed. Below this level a retention of the debris flow occurs. Using the model the process of debris flow and the impact on the construction work could be simulated well.

Beurteilende(r): Hübl Johannes
1.Mitwirkender: Chiari Michael

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