An Experimental Study on Mechanisms for Sediment Transformation Due to Riverbank Collapse

Abstract

Riverbank erosion is a natural process in rivers that can become exacerbated by direct and indirect human impacts. Unfortunately, riverbank degradation can cause societal impacts such as property loss and sedimentation of in-stream structures, as well as environmental impacts such as water quality impact. The frequency, magnitude, and impact of riverbank collapse events in China and worldwide are forecasted to increase under climate change. To understand and mitigate the risk of riverbank collapse, experimental/field data in real conditions are required to provide robust calibration and validation of hydraulic and mathematical models. This paper presents an experimental set of tests conducted to characterize riverbank erosion and sediment transport for banks with slopes of 45 • , 60 • , 75 • , and 90 • and quantify the amount of sediments transported by the river, deposited within the bank toe or settled in the riverbed after having been removed due to erosion. The results showed interesting comprehension about the characterization of riverbank erosion and sediment transport along the river. These insights can be used for calibration and validation of new and existing numerical models.

Laboratory Experiments of Bank Collapse: The Role of Bank Height and Near‐Bank Water Depth

“…On the other hand, an increase in H w implies a larger hydrostatic pressure, providing supporting forces that reduce the frequency of bank collapse. Figure 9a shows the correlation between the ratio H b /H w and the normalized bank retreat rate (equation 1 and section 2.3), using data from the present (Figure 4 and Table 4) and previous studies (Patsinghasanee et al, 2017;Qin et al, 2018;Shu et al, 2019;van Dijk et al, 2012;Wells et al, 2013). In the above studies banks are mainly composed of silt and sand, and detailed information of variables for each experiment is shown in Table S1 in the supporting information.…”

“…Fundings from Postgraduate Research and Practice Innovation Program of Jiangsu Province (KYCX18_0606) and National Natural Science Foundation of China (51739005) are gratefully acknowledged. The data used in this study (Figure 9) are extracted from van Dijk et al (2012) (Doi:https://doi.org/10.1029/2011JF002314), Wells et al (2013) (Doi:https://doi.org/10.1016/j.catena.2012.10.004), Patsinghasanee et al (2017) (Doi:https://doi.org/10.1016/j.jher.2017.04.002), Qin et al (2018) (Doi:https://doi.org/10.1016/j.still.2017.12.008), and Shu et al (2019) (Doi:https://doi.org/10.3390/w11030529).…”

Mechanisms for avulsion on alluvial fans: insights from high-frequency topographic data

“…Longoni et al, 2016;Rinaldi and Darby, 2007;Cashman et al, 2018). Sediment generated by bank erosion may be directly entrained into the flow or deposited on the bed (Grissinger et al, 1991;Shu et al, 2019). The volume and size of material input to the channel will control whether the material aggrades the bed or is transported downstream (Rinaldi and Darby, 2007;Swartenbroekx et al, 2010).…”

Protecting Coastlines from Flooding in a Changing Climate: A Preliminary Experimental Study to Investigate a Sustainable Approach

“…Studies conducted to date have confirmed that tsunamis and storms have generated washover deposits across beaches or dunes in the last decade [101]. The deposition of sediments therefore continues to alter the morphology of coastal areas after each storm event [102][103][104][105][106][107][108], penetrating into existing material and causing various levels of stratification which vary the permeability of the site. This is another aspect that was beyond the scope of this study but would require the characterization of sedimentary characteristics of varius type of washover successions for multiple coastal tophography configurations, including the beach ridge elevation and backshore tophography.…”