Debris Flow Mitigation With Flexible Ring Net Barriers – Field Tests And Case Studies
Free (open access)
23 - 31
C. Wendeler, B. W. McArdell, A. Volkwein, M. Denk & E. Gröner
A new type of debris flow mitigation measure, flexible ring-net barrier systems, are cost-effective and efficient compared to massive concrete barriers. However, the performance of these systems has not yet been investigated systematically. For this reason a wire ring-net barrier system has been installed in the Illgraben torrent, to investigate its performance, measure the forces and to provide information on the expected maintenance. Additionally, this net-testing facility allows for optimization of the structure and provides a basis for design guidelines. This paper describes the measurement facilities at the barrier and the debris flow events of 2006. First results of the filling event and their interpretation with the computational model are discussed. Keywords: debris flow mitigation, flexible debris flow barriers, numerical simulation, field testing. 1 Introduction Debris flows are initialised mostly by heavy rainfalls where the water quickly infiltrates into and mobilizes the ground material in mountainous regions. They flow downwards in riverbeds and along slopes, carrying large blocks and boulders, and endanger humans and their infrastructure. To reduce debris flow damage adequate protection measures have to be chosen. In regions where large debris flows occur frequently the best protection measures are typically large dams to re-route the debris to less vulnerable areas or special retention basins. But for smaller volumes a new protection system, the flexible ring-net barrier (Fig. 1), is now in a testing and developing phase in Switzerland. As shown here,
debris flow mitigation, flexible debris flow barriers, numerical simulation, field testing.