Effect of bed roughness on the hydrodynamic properties of dam-break waves

A dam-break wave can result in considerable damages and casualties. Events that can lead to such waves include dike and dam breaches, storm surges and impulse waves. Dutch history is familiar with a number of coastal dike breaches but also river dike breaches have occurred, resulting in dam-break waves reaching far inland. Beyond the Netherlands...

Calculation of dam risk probability of cascade reservoirs considering risk transmission and superposition

Because of the risk transmission and superposition among dams in cascade reservoirs, the analysis and probability calculation of dam risk become more complex compared with a single reservoir. By analyzing the main risk sources and actionmechanisms, the disaster-causing factors, disaster-transmitting body and disaster-bearing body in the cascade...

Effect of bed roughness on tsunami bore propagation and overtopping

The accurate modelling of overtopping of coastal defences by tsunami waves is of vital importance for the formulation of disaster management strategies. To improve knowledge of this phenomena the authors conducted experiments on coastal structure overtopping using bores that were generated by a dam-break mechanism. Three types of structures...

Hydrodynamic Loading of Dutch terraced houses due to flood actions using Computational Fluid Dynamics

Whenever a region - especially the coastal area - is affected by flood risk, it is essential for residential and life protection to gain knowledge about the mechanisms leading to the collapse of houses. There are empirical mortality functions to predict the mortality of population in the Netherlands directly affected by flooding, but due to...

Improved set pair analysis and its application to environmental impact evaluation of dam break

Despite the rapid development of risk analysis in dam engineering, there is a relative absence of research on the environmental impact of dam break. As a systematic theory, set pair analysis has a good effect in dealing with uncertainties, although the result is relatively rough and easy to distort. A connection degree of five grades and a...

Risk evaluation model of life loss caused by dam-break flood and its application

The internal mechanism affecting life loss caused by a dam-break flood is complicated. On the basis of analyzing the risk formation path, a risk evaluation indicator system was established which included the hazards, exposure and vulnerability factors. Variable Fuzzy Sets theory was introduced into the risk evaluation of life loss risk grades...

On the rheological characterisation of liquefied sands through the dam-breaking test

This paper concerns the rheological characterisation of liquefied sands as non-Newtonian Bingham fluids. For this purpose, dam-breaking laboratory tests are often executed and interpreted, offering a viable option to identify the properties of fluidised water-soil mixtures. However, limited attention has been devoted so far to clarify what...

Tsunami Bore Overtopping Of Coastal Structures

In the aftermath of the 2011 Tohoku Earthquake and Tsunami Japanese tsunami protection philosophy now dictates that coastal defences should prevent the land that they protect from being flooded under a Level 1 event (with a return period in the order of about 100 years). To ascertain the overtopping mechanism and leeward inundation heights of...

Overtopping of coastal structures by tsunami waves

Following the 2011 Tohoku Earthquake and Tsunami, Japanese tsunami protection guidelines stipulate that coastal defences should ensure that settlements are shielded from the coastal inundation that would result from Level 1 tsunami events (with return periods in the order of about 100 years). However, the overtopping mechanism and leeward...

Analysis of green water events on a typical FPSO design

This study dealt with the problems caused by green water waves, waves that reach so high that significant overflow onto the deck occurs. The most important hazard caused by green water is the direct impact load on deck, threatening equipment, hull structure and personnel. The goal of current green water research is to be able to (better) predict...

Analysis of green water events on a typical FPSO design

This study dealt with the problems caused by green water waves, waves that reach so high that significant overflow onto the deck occurs. The most important hazard caused by green water is the direct impact load on deck, threatening equipment, hull structure and personnel. The goal of current green water research is to be able to (better) predict...

Mathematical modelling of morphological changes and hyperconcentrated floods in the Yellow River

Hyperconcentrated flow/flood is a water-driven sediment transport phenomenon, which is characterized by high sediment concentrations between normal sediment-laden flow and debris/mud flow. In a hyperconcentrated flow, strong interactions exist between water flow, sediment, and river bed, which may not only change the flow rheological properties,...

Morphological modeling using a fully coupled, total variation diminishing upwind-biased centered scheme

High-resolution morphological modeling of fluvial processes with complex, rapidly varying flows has been limited so far by model accuracy or computational efficiency. One of the most widely used numerical algorithms is based on the total variation diminishing method, solved by either upwind or centered approaches. An upwind scheme preserves high...

Implementation of a wetting and drying algorithm in a finite element model

In numerical modelling of water movement wetting and drying is a well known problem. The governing equations are not valid in the dry part of the computational domain which may result in problems with mass conservation, negative water depths and artificially enlarged gradients. A method is proposed that allows for the surface elevation to become...

Breach Initiation and Growth: Physical Processes

During the IMPACT Project a number of large scale field tests were undertaken in Norway to collect data, including extensive video footage, recording the physical processes that occured during the initiation and growth of breach through the test embankments. The video footage has been carefully analysed and key processes identified, to support...

Modelling Breach Initiation and Growth

This report provides an overview of the technical work undertaken by the partners under FLOODsite Task 6. The research in Task 6 addresses breach initiation and growth. Research was undertaken to (i) investigate and develop preliminary models for predicting wave induced breach initiation (ii) investigate soil processes, review and refine the HR...

Dam break modelling, risk assessment and uncertainty analysis for flood mitigation

In this thesis a range of modelling techniques is explored to deal effectively with flood risk management. In particular, attention is paid to floods caused by failure of hydraulic structures such as dams and dikes. The methods considered here are applied for simulating dam and dike failure events, flood water routing in downstream areas, and...