Effect of plan layout on the sediment control efficiency of slit-check dams for stony type debris flows mitigation

Abstract

There has been an increasing acknowledgement of debris flows as one of the most relevant geomorphic modifiers of many steepland valleys and fans. Despite it being a well-known phenomenon, debris flows are somehow unpredictable and complex to simulate. Due to several past harmful debris flows worldwide, there are already a significant number of mitigation structures with water and sediment control functions, which are essential features of short-term countermeasures against debris flows. This paper is based on laboratory experiments carried out to test slit dams (open-type retention dams), usually used as a structural countermeasure to mitigate debris flows in steep torrential channels. Flume tests were conducted using a straight channel to assess the influence of different slit-dam solution types on the sediment retention efficiency against stony-type debris flows. Inspired by common slit dam solutions, two different piers layouts in plan view were tested. The experiments were performed with two different discharges and two different slopes. Experimental results about the sediment control efficiency are presented for the different tested solutions.

Contributos para uma estratégia integrada de gestão do risco de aluviões na ilha da Madeira

“…Os troços de ribeira objeto de monitorização devem incluir as infraestruturas de retenção de material sólido para avaliar o seu desempenho na retenção da fase sólida do escoamento, e dessa forma complementar o trabalho de modelação física realizada em laboratório (Silva et al, 2015;2016). A análise conjunta destes elementos pode conduzir a melhorias significativas dos critérios de dimensionamento destas intervenções e a eventuais medidas de aperfeiçoamento nas obras já construídas.…”

Model-based approach for design and performance evaluation of works controlling stony debris flows with an application to a case study at Rovina di Cancia (Venetian Dolomites, Northeast Italy)

“…Depending on it, such a dam can partially or entirely trap the debris flow front characterized by the material of the coarsest size (Piton and Recking, 2016). A more simplified view associates sectional dams with slit dams characterized by a unique opening, usually placed at the center (Silva et al, 2015). In the present work, we prefer to use the term sectional dam.…”

Method for Evaluating the Trapping Effects of Woody Debris Using a Distinct Element Method

“…Thus, a numerical simulation to settle this issue should be applied to investigate the trapping mechanism. Many studies of open Sabo dams have been carried out [Ishikawa et al ., 1988 ;Mizuyama, 2008Mizuyama, , 2010Silva et al ., 2015]. In particular, Shima et…”