Model of erosion–landslide interaction in the context of the reservoir water level variations (East Siberia, Russia): Factors, environment and mechanisms

Abstract

A comprehensive investigation of landslide-erosion interactions has been carried out in the local shore geosystem of the Bykovo site located on the left shore of the Bratsk reservoir. The landslide process develops in the Mid-Quaternary grounds (aQ 3 II ) of the erosion-accumulative terrace's fragment that comprises sand, sand with pebbles, sandy loams and loams. This study aims to assess the environmental factors of interacting landslide and gully erosion processes, to estimate their temporal dynamics by comparative analysis of cartographic models based on the data of repeated theodolite surveys, and to find out what level regime of the reservoir stimulates the activation of the landslide process. The authors propose two-stage descriptive model of erosion-landslide interaction and development mechanisms in the context of the reservoir water level variations in the Bratsk reservoir. The activation of landslide processes in the reservoir shores follows the periods of high water level stands. Shore slope stability is disturbed by abrasion of slope foot and inundation of the slide zone. The soils subject to landslide, erosion-landslide and erosion processes differ in their microstructure and properties. Largest erosion susceptibility is typical of soils with skeleton-aggregated microstructure, fine-and coarse-silt sandy loams and loams of high porosity, whose interstructural bonds are attributed to water-soluble salts (Sws = 0.4-0.5%) and high carbonate contents (Scr = 34-66%). High dispersion and aggregation of clay fractions is typical of the loams of the slide zone. The structure of soils subject to deformation slide is represented primarily by fine-sand particles and aggregates with smaller cohesion and strength properties. erosion-landslide interaction can be related to the hillslope-to-channel coupling in local scale.

Investigation of seepage effect on river dike’s stability under steady state and transient conditions

“…Breach mechanism is classified as following: hydraulic failure, geo-hydraulic failure and global static failure, [20]. Hydraulic failure generally consists on overtopping [21] and wave scour on the dike structure, while geo-hydraulic failure is due to the seepage process through the dike core or foundation, which leads into the erosion process associated with transportation of significant materials amount.…”

Analysis of deformation characteristics and stability mechanisms of typical landslide mass based on the field monitoring in the Three Gorges Reservoir, China

“…Field investigations (Ocakoglu et al 2002(Ocakoglu et al , 2009Gokceoglu et al 2005;Pradhan et al 2010;Hu et al 2015) and numerical simulations (Alemdag et al 2014;Longoni et al 2014;Zhang et al 2017) are widely used to study the deformation and stability mechanisms of landslide mass. Moreover, the field monitoring of the surface displacement has also been applied by some researchers (Lee 2004;Panizzo et al 2005;Su et al 2009;Fan et al 2010;Zhang et al 2010;Mazaeva et al 2013;Tang et al 2015;Xia et al 2015;Renato et al 2016). However, the recent studies have paid little attention to applying an integrated monitoring system to a single landslide.…”

Spatiotemporal distribution and failure mechanism analyses of reservoir landslides in the Dagangshan reservoir, south-west China

“…A large number of massive hydropower stations have been constructed in south-western China, including the Jinping-I and Jinping-II Hydropower Stations on the Yalong River, the Dagangshan Hydropower Station on the Dadu River, the Maoergai Hydropower Station on the Heishui River and the Three Gorges Hydropower Station on the Yangtze River (Zhou et al 2010;Jiao et al 2014;Gui et al 2016;Yin et al 2016). After the construction of a high dam, the water storage and constantly fluctuating water have an adverse influences on slope alone the river banks and lead to changes in the local climate and ecological environment (Wang et al 2004;Mazaeva et al 2013;Zhou et al 2016b) to accelerate the adverse influences on safety of slope (Hu et al 2015;Babanouri and Dehghani 2017;Sun et al 2017). These reservoir landslides pose a great threat to the safety of hydropower stations (especially high dams), coastal infrastructure and human life.…”