University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Lisa Maria Pfann
(2017):
Abflussberechnung am Mödlingbach nach Revitalisierungsmaßnahmen im Stadtgebiet von Mödling.
Master / Diploma Thesis - Institut für Hydraulik und landeskulturelle Wasserwirtschaft (IHLW),
BOKU-Universität für Bodenkultur,
pp 93.
UB BOKU
obvsg
FullText
- Abstract:
- After accomplishing the revitalization measures at the Mödlingbach on a 907 m long river reach, located in the urban area of Mödling, a hydraulic 1-D model was utilized to calculate the water levels of flood events. Furthermore, the goal of this master thesis was to compare this simulation of 2017 adopting insitu measured geometry data with the simulation of 2007 using “as planned” geometry data during the revitalization measures. The specific measures of biological engineering, which were realized in 2016 due to the revitalization, and hydraulic relevant elements like bridges or ramps are described. To obtain actual cross section data for the simulation the river reach was new surveyed. The surveyed river reach is shorter than the one of the model of 2007, but the simulation model in this thesis contains much more measured cross sections and therefore a more detailed geometry. The boundary conditions and roughness values were set similar to the original project. Simulations showed that the water level of a 100-year flood is 35 cm lower using more detailed and refined geometry data after implementation of revitalization compared to the 2007 simulation. The higher levels in the 2007 model is caused by an occurring backwater at the Gymnasiumbrücke. The new simulation showed a water level at the same height of the lower edge of the bridge or rather the lower bottom of the pipes that are fixed on both sides of the bridge. This lower water level on the upstream side of the bridge is a result of the observation of a critical depth, which appears at the ramp right downstream the bridge. However, the fact that a flood event occurs without hitting the bridge doesn’t claim that this river reach is flood-proof. Since physical factors like wave oscillation or conveyed dead wood are not considered in the simulation model an additional safety freeboard between the water level and the lower edge of the bridge is mandatory.
- Beurteilende(r): Loiskandl Willibald
- 1.Mitwirkender: Florineth Florin