We have developed a "Soft Rocks Riverbed Evolution Model" that can calculate 1) Rock wear caused by gravel and running water, and 2) Rock erosion caused by slaking due to repeated drying and wetting. This model is based on a two-dimensional riverbed evolution analysis model that can calculate river flow and sand and gravel transportation during floods.

In rivers where bedrock is exposed, riverbed degradation due to rock erosion can lead to insufficient foundation of revetments, impeded water use, and deterioration of the habitat of living organisms, and measures to prevent riverbed degradation are therefore required. One method for implementing effective measures to prevent riverbed degradation is to predict and evaluate the effectiveness of measures using a numerical analysis model. However, we felt that a general two-dimensional riverbed evolution analysis model cannot reliably predict changes in river channels, including rock erosion.

Based on the above, we have developed a "soft rocks riverbed evolution model" to study effective riverbed lowering countermeasures even in rivers with exposed bedrock and to predict and evaluate the effectiveness of the countermeasures. This model not only allows for the analysis of the current river channel in rivers with exposed bedrock, but also makes it possible to predict the future of the river channel.

For details on the "Soft Rocks Riverbed Evolution Model", please see the link below.
https://www.jstage.jst.go.jp/article/river/28/0/28_307/_article/-char/ja/

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■ Contact point regarding model inquiries
Hiroki YOSHITAKE, Water Course Engineering & Water Resources Dept., Land Infrastructure Div.: hiroki.yoshitake@tk.pacific.co.jp
Masashi MINAMI: masashi.minami@ss.pacific.co.jp