Modelling of undercutting and failure of non-cohesive riverbanks

River morphodynamics and sediment transportBank erosion and protectio

Estimation of the Wall Shear Stress on a Natural Riverbank

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

First Results of Modelling Benthos Influence on Sediment Entrainment Using a Generic Approach within the MOSSCO Framework

Sediment Transport and Morphodynamic

The Predominant Processes Controlling Vertical Nutrient and Suspended Matter Fluxes across Domains - Using the New MOSSCO System from Coastal Sea Sediments up to the Atmosphere

Integrated Modeling of Hydro-System

The Benthic Geoecology Model Within The Modular System For Shelves And Coasts (MOSSCO)

The Modular System for Shelves and Coasts (MOSSCO) integrates physical, biological, chemical and geological models of shelves and coasts for the North Sea and Baltic Sea in an exchangeable way. The MOSSCO software forms a coupling framework for exchanging data and models, which distinguishes between physical domains (Earth System compartments such as the benthic and pelagic zone) and processes (such as benthic geochemistry, physical erosion and biological stabilization). Information exchange across physical domains with different grids and time steps are managed using the ESMF (Earth System Modelling Framework), whereas coupling of processes within individual modules is achieved using FABM (Framework for Aquatic Biogeochemical Models). This paper reports coupling of a newly developed benthic geoecology model to the MOSSCO framework. This new model incorporates the biological effects of macrofauna (the bivalve Tellina fabula is taken as an example) and microphytobenthos on erodibility and critical bed shear stress. The model is implemented in an object-oriented generic modular way so that it can be extended to any number of biological effects on the sediment transport for an arbitrary number of species. Finally, the application of the coupled model is demonstrated in simulation of a1D setup

Böschungserosion in alluvialen Gewässern mit nicht kohäsiven Boden bei instationären Strömungen

Bislang ist die Theorie der Böschungsbruchvorgänge für kohäsionslosen Boden auf ebenen Gleitfugen in einem rollenden, nicht verdichteten und voll gesättigten Boden mit diskreten Körnern begrenzt und damit vor allem für Kiesboden anwendbar. Die vorliegende Felduntersuchung hat aber gezeigt, dass Unterspülung und Gleitfugen unterhalb des Wasserspiegels sowie Abbruch der Überhänge die dominanten Prozesse im kohäsionslosen verdichteten (sandigen) Boden unter instationären Bedingungen sind. Diese Prozesse wurden in der vorliegenden Arbeit durch eine innovative Methode modelliert, die durch Feldmessungen validiert wurde. Die Ergebnisse zeigten, dass diese Methode die Genauigkeit der Simulation im Vergleich zu den bisherigen Methoden bis zu sechsmal verbessert.So far the theory of bank failure in non-cohesive soils is limited to the avalanche of loose, not compacted, fully saturated discrete grains, applicable mainly to gravel banks. However, the present field investigation indicated that undercutting of the riverbank, slip failure of the submerged zone of the bank, as well as cantilever failure of the overhang are the dominant processes in non-cohesive dense (sandy) soils under unsteady flow conditions. These processes have been modelled in the present work by an innovative method, which has been validated by field measurements. The results showed that the method enhanced the simulation accuracy up to six times in comparison to the earlier methods