Einfluss der Breschenbildung auf die Flutwellenausbreitung bei Damm- und Deichbrüchen

Within the framework of risk assessment for dams and dikes the probability of a failure as well as failure processes and consequences have to be analysed and evaluated. Therefore, this study deals with the computational modelling of breach formation and flood wave propagation at dams and dikes including the determination of uncertainties connected to the predicted flow depths, flow velocities and damage related factors. A hybrid model has been developed, which links the two-dimensional, unsteady simulation of the flow to a one-dimensional, parametric modelling of the breach formation. Comparisons to laboratory and field data allow for a detailed calibration and validation of the new model. Due to the specification of geometrical and geotechnical parameters, the results obtained still incorporate uncertainties. In a first step, decisive factors of influence are identified by a sensitivity analysis. In case of a dike-break the outflow is less sensitive to defined parameters than the dam-break outflow. In order to investigate the uncertainty, probability density functions of the main influencing factors are derived from failures in reality as well as from literature. An uncertainty analysis based on the stochastic response surface method is performed to quantify the influence of breach formation on the results of the flood wave propagation for dams and dikes. Thus, probability density functions of the risk relevant results are determined allowing for a detailed description of uncertainties. A synthetical test case for dike-breaks shows a relatively small uncertainty of the computed water level and flood extent. By means of an actual example for dam-breaks the reduction of the uncertainties in the results with increasing distance from the dam is determined. For all results the obtained probability density functions show an advantageous distribution to identify the critical values, which are in demand within risk analysis. The significance and effects of the incorporated uncertainties can still vary according to the test case conditions and specific land use in the area at risk. The integration of an uncertainty analysis for flood propagation modelling in risk analysis is recommended. Moreover, for all components of risk assessment procedures, uncertainties should be determined in order to compare the quality of the different results and also to obtain probability based information about the risk.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2007

Author dc:creator

• Niemeyer, Maren

Contributors dc:contributor

• Köngeter, Jürgen

• info:eu-repo/classification/ddc/620
• Deichbruch
• Dammbruch
• Unsicherheit
• Flutwelle
• Risikoanalyse
• Überflutung
• Ingenieurwissenschaften
• Bresche
• breaching
• risk assessment
• failure
• dam
• dike

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124070%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:62504