Abstract
In recent years, the intensified influences of global climate change and human activities have increased the frequency of large-scale debris flow disasters. As a result, main river channels often become blocked, thus forming a disaster chain of rivers dammed by debris flow followed by outburst flooding. In order to quickly and easily reveal the dynamic process of a debris flow dam breach, and quantitatively predict the outburst flood hazard, this study takes the Zhouqu “8.8” debris flow barrier dam in Western China as an example. Based on a stability assessment, China Institute of Water Resources and Hydropower Research’s Dam Breach Slope (DBS-IWHR), China Institute of Water Resources and Hydropower Research’s Dam Breach (DB-IWHR), and Hydrologic Engineering Center’s River Analysis System (HEC-RAS) were integrated to simulate the development of dam breach, breach flood, and outburst flood evolution, respectively, under different scenarios. The simulated peak discharge flow of the actual spillway was 317.15 m3/s, which was consistent with the actual discharge of 316 m3/s. The results under different scenarios showed that, with the increased inflow of the barrier lake, the erosion rate of the dam increased, the peak discharge of the dam break flood increased, the peak arrival time shortened, and the downstream flooding area increased. These findings could provide scientific support for risk management and emergency decision-making with respect to barrier dam failure.
Highlights
By comparing scenarios 1 and 2, it can be seen that when the inflow of the barrier lake increased by 506%, the peak discharge of the dam-break flood increased by 243%, while the arrival time of the flood peak reduced by 31%
When the inflow of the barrier lake increased by 506%, the peak discharge of the dam-break flood increased by 243%, while the arrival time of the flood peak reduced by 31%
The Zhouqu debris flow was used as an example in this work to assess dam stability based on the geomorphological index method
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Fan et al [32,33] established a comprehensive numerical modeling method for the landslide-dam breach-flood disaster chain through Massflow, the DABA, and HEC-RAS models, and successfully applied it to the Baige landslide of the Jinsha River These studies provide an important basis for the risk evaluation of outburst flooding due to debris flow dam breaks. In order to evaluate the failure of debris flow dam-outburst flood hazard chain under different scenarios in the Bailong River basin and establish a method for the rapid evaluation of the risk associated with this hazard chain, this study takes the Zhouqu “8.8” debris flow hazard chain as an example We achieve this using the DBS-IWHR, DB-IWHR, and HEC-RAS multi-model. This study could provide a relevant reference for the emergency response, risk assessment, and management of debris flow-dam breach-outburst flood hazard chain events in the Bailong River basin and similar areas
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.