Laboratory study related to performance increment of flexible network barrier against debris flow

Document Type : Original Article

Authors

1 Department of Water Engineering, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, Iran;

2 Assitant Professor. Department of Water Engineering, Shahid Bahonar University of Kerman., Kerman., Iran

Abstract

Flexible debris flow barrier is defined as a type of risk reduction structure against debris flow, which is more economical than concrete barriers. The mentioned barrier has been successfully applied to decrease or even stop the debris flow volume without downstream damage. Performance of the barrier in order to control the full gravel debris flow were examined in a laboratory flume. Then, specific parameters were listed and based on dimensional analysis, behavior of this structure against full gravel debris flow has been programmed, identified and tested using dimensionless criteria. The results of the experiments indicated acceptable performance of network barrier with different opening and geometry against various flow concentrations and debris flow velocities. Moreover, the results showed that the flume slope is a criterion for expressing the flow velocity, and tracks type on the barrier are the most effective factors on the barrier performance. An increase of 25 percent in the accumulated debris height parameter has been occurred with a change of 2 degrees in the flume slope. Decreases equal to 7 and 12.5 percent in the length range parameter of the debris accumulation upstream of the barrier have been observed by the experiments with a change in position of the vertical tracks embedded on the barrier. Moreover, pressures on the barrier are calculated in each flow, which can be actually effective in designing the correct barrier.

Keywords


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