The Masch(a)nserr(u)fe project-A system of debris flow discharge and volume control
In the Masch(a)nserr(u)fe torrent area of Graubu¨nden, Switzerland, debris flows occur frequently and endanger several important transportation lines at the toe of its fan. For protection, a large sediment retention basin wasbuilt at the fan apexin 1964. Althoughretaining everydebris flowsince, this solution has resulted in large annual costs of debris removal from the basin. The present requirements are (1) to optimize the basin, in terms of debris flow passage and retention by minimizing the risks to the downstream infrastructure, (2) to minimize the costs for debris removal, and (3) to increase the sediment input into the receivingRhineRiver tohelp reduceacute river bederosion in that river. Asolution of debris flow discharge and volume control was developed and tested with the help of physical and numerical modelling. Discharge control is achieved in the sediment retention basin by dosage channels with confined flowcapacity and lateral weirs. If debris flowdischarge exceeds the flowcapacity of the dosage channels, debris is diverted into the basin. Hence, the outflowfrom the basin is limited. Volume control is activated after the passage of a critical debris flow volume. This requires the measuring debris flow volumes by appropriate methods. Discharge control has already been implemented and its effectiveness during two events has been confirmed. Volume control has not yet been implemented.
debris flow mitigation debris flow control risk management
M. Schatzmann C. Tognacca G.R. Bezzola A. Bischoff
Basler & Hofmann Consulting Engineers AG, Esslingen, Switzerland BeffaTognacca GMBH, Rotkreuz, Switzerland Federal Office for the Environment, Bern, Switzerland Cantonal Office for Civil Engineering, Chur, Switzerland
国际会议
成都
英文
669-679
2007-05-17（万方平台首次上网日期，不代表论文的发表时间）