Coastal Flood Risks Under Extreme Waves: Creating Resilience through Retrofitting - Living With Environmental Change (LWEC) - Coastal and Waterway Eng

点击翻译按钮获取中文摘要

Scientific context of the study: The maintenance of the coastal defence structures imposes huge costs to the coastal communities. For example, the total length of the UK's coastline is almost 12 500km, and in England & Wales 44% of the coastline is defended (6% in Scotland) against natural forces, costing approximately £358m each year to maintain, with total replacement costs in excess of £20 billion. Projections are that spending on coastal defences will need to double by 2080 to maintain the present coastline. As engineers struggle to maintain traditional 'hard' defences, such as rock walls, armour or embankments, 'soft' engineering solutions, including the recreation of foreshores and beaches, are rapidly finding favour. The intention of this PhD study is to investigate the effects of climate change (e.g. the combined effects of sea level rise and the now more where gaps in knowledge are known to exist. For typically natural soft defences, the research will address the effects on run-up, wave impact and wave over-wash through a range studies, such as natural beach shape optimization in front of rock-armoured revetments.The State of the Nation: Infrastructure 2014 (ICE, 2014) reports that Flood Management infrastructure is infrequently maintained and requires attention. The resilience of these structures to the severe weather events is more important because they protect other infrastructure networks from disasters. Current design guidance (e.g. Levee Handbook, CIRIA C731 & EurOtop) predominantly focuses on simple geometric hard defence configurations. In the absence of detailed numerical or physical models, for complex geometries or softer natural defence configurations, engineers currently have to make rudimentary assumptions from current guidance. This leads to large levels of uncertainly in where, when, and how the damages may occur. This does little for the confidence of local authorities and communities in regard to planning, adapting, and mitigating the effects of disasters.Methodology, and expected results: A number of different case studies will be selected for analysis, giving due considerations to the time and budget constraints. Achieving a good variety between cases is important; in order to achieve a holistic image of morphological changes in different environments.Different scenarios will be developed, based on the available projections for sea level rise and storm events. Numerical simulations will be conducted for all the developed scenarios, using available models such as SWAN for wave propagation and XBeach for bed updating.Comparisons between different cases and scenarios can be used to determine the significance and the sensitivity of each variable, by carrying out a number of simulations.Laboratory testing will be used for calibration and validation of the developed models, and in this task, University of Warwick plays an important role due to its availability of access for good physical modelling facilities. The uniqueness of the methodology will be achieved by integrating existing methods to provide answers to climate change and sea level rise problems.Significance: Outcomes of this study are expected to provide insights to substantially fulfil the existing knowledge gap related to the impacts of climate change on the morphological variations around rubble mound structures.Currently, the projections of possible climate change induced impacts are considered when designing and constructing new rubble mound structures. However, the available projections mainly cover the sea level rise (reliably) and the increased intensities of tropical cyclones/hurricanes/typhoons (doubtfully). The outcomes of this PhD vastly improve design methodologies to resist the probable morphological changes around the revetments and breakwaters, which will lead to the creation of a safer coastal environment for future generations.