Research students - Infrastructure and built environment

• PhD Student: Alfred Ndhai Jones
• Supervisors: Prof John Bridgeman
• Duration: 2013-2016

The growing concern about clean water supply in less-developed countries has triggered innovative research to find potential alternatives to traditional approaches to water treatment. Water treatment in any part of the world is aimed at providing the population with clean and safe drinking water free from pathogens and other disease-causing organisms. Access to safe drinking water improves health, wealth and productivity. However, this life-sustaining commodity is unavailable in many communities across the globe. To tackle this challenge, the World Health Organisation (WHO) formulated a program to alleviate drinking water supply problems worldwide through the millennium development goals (MDGs) and subsequent sustainable development goals, which stipulates the halving of the population without access to clean drinking water. To date, over 663 million inhabitants of third world countries still do not have access to safe and improved drinking water.  

This study considers the suitability of native plant seeds for point of use water treatment in developing countries in order to enhance our understanding of the use of naturally-occurring plant extracts for water treatment. Specifically, the research is exploring the potential and effectiveness of Hibiscus plant seed species as novel coagulants in drinking water treatment. The outputs will assist people in rural areas of developing countries to have access to a clean source of drinking water avoiding the difficulties associated with conventional methods. 

• PhD Student: José Carlos Nogueira Filho
• Supervisors: Prof John Bridgeman & Prof Mark Sterling
• Duration: 2015-2019

Mesophilic anaerobic digestion is the most widespread technology for the treatment of sewage sludge, a by-product of wastewater treatment. Sludge is mixed with anaerobic bacteria at temperatures between 22 and 41 degrees Celsius, and biodegradable material is broken down into more stable compounds, producing a methane-rich biogas during the process. Biogas, in turn, is increasingly harnessed as a renewable energy by means of combined heat and power technology. In order to understand how to enhance digester mixing, it is important to determine to what extent biogas output is influenced by flow patterns in a digester; flow patterns which are determined by physical parameters of the digesters, inflow mode, sludge rheology and, crucially, mixing regimes. However, research is still lacking in this area. Traditional approaches to digester design are firmly rooted in empiricism and rule of thumb rather than science, and design standards focus only on treated sludge quality, not quality and gas yield/energy consumption.

This project aims to enhance biogas output of anaerobic digesters through an analysis of the sludge flow patterns during mixing. Two-phase (liquid-solid) and three-phase (liquid-solid-gas) computational fluid dynamics (CFD) models will be built to investigate the interactions between mixing, sedimentation and biogas production. Lab-scale experiments will be undertaken to ensure model validation. 

• PhD Student: Aryan Hojjati
• Supervisors: Prof Ian Jefferson & Dr Nicole Metje
• Duration: 2014-2017

The utility infrastructure is a critical element of urban environments. However, utility installation and maintenance operations are costly, both in terms of direct construction costs (~ £1.5 billion in the UK in 2006) and in terms of indirect and social costs (~ £5.5 billion per year in the UK in 2006), which adversely impact the UK economy. These costs are significantly increased when the considerable environmental costs are considered. These adverse impacts are mainly due to traffic congestion, both in terms of energy wasted and vehicle emissions. It is now established that the true total cost of any activity can only be measured by considering all aspects encapsulated by the three ‘pillars of sustainability’, i.e. taking account of social and environmental impacts along with economic (both direct and indirect) costs.

The aim of this research project is thus to develop a sustainability costing model and evaluation methodology for Utility Streetworks that will allow alternative intervention approaches (e.g. Trenchless Technologies and Multi-Utility Tunnels) to be assessed by comparing the true total (i.e. economic, social and environmental) cost / impact.  It will thus provide a basis on which to support investment decisions for streetworks projects which itself provides the final piece of the jigsaw in informing engineers of the likely outcomes of their actions.

• PhD Student: Nick Tziavos
• Supervisors: Dr Hassan Hemida, Prof Charalampos Baniotopoulos, Dr Nicole Metje 
• Duration: 2014-2017

Offshore wind energy is a growing sector in the UK with over 1400 wind turbines operating. Nowadays, monopiles are the simplest and most common structure employed in offshore wind farms. They are formed of large-diameter cylindrical steel tubes and grouted connections are used to attach them by filling the annuli between them with high-strength cementitious grout. Several implications related to the connections were recently reported in wind farms all over Europe owing to insufficient design. This research project aims to investigate the performance of grouted connections to provide an improved understanding of their actual behaviour. Current standard codes lack sufficient guidance on the design of grouted connections using numerical models. Hence, finite element models are developed and validated against experimental data. Based on the developed non-linear finite element models various parameters affecting the performance of the connections, such as shear keys and overlap length are investigated.

• PhD Student: Saif Alzabeebee
• Supervisors: Prof David Chapman, Dr Asaad Faramarzi, Prof Ian Jefferson
• Duration: 2014-2017

Buried pipelines are vital to maintaining modern life. They are widely used for drainage and sanitary applications, as well as transporting products such as gas and water. However, buried pipelines have not received significant attention from researchers in the UK to improve their design, and understand their behaviour, under UK traffic loading conditions for both rigid and flexible pipes. Therefore, this research aims to improve the design of buried pipes using robust and accurate analysis via a three-dimensional numerical model and an advanced data mining technique.

The outcome of this research will be a significant contribution to the understanding of the response of buried pipelines under soil loading and the UK standard traffic loading, and robust design models derived using an advanced data mining technique. This will therefore provide enhanced safe, robust and economical design approaches for rigid and flexible pipes.

• PhD Student: Ridwan Abdul Rahman
• Supervisors: Dr Samir Dirar & Dr Marios Theofanous
• Duration: 2012-2016

Beam-column (BC) joints play an important role in the seismic performance of moment-resisting reinforced concrete (RC) frame structures. Without proper design and detailing of the joint shear reinforcement, as the case is with RC buildings designed according to the pre-1970s building codes, RC connections can be the most vulnerable elements during an earthquake and can undergo joint shear failure. Practical and effective techniques are therefore required for strengthening shear-deficient RC BC joints. 

The use of fibre reinforced polymer (FRP) strengthening techniques has gained interest due to the excellent mechanical and durability properties of the FRP composites. However, experimental results have shown that FRP de-bonding remains the main drawback preventing the utilisation of the high tensile strength of the FRPs. When un-anchored externally bonded (EB) or near-surface mounted (NSM) FRP reinforcement is used, de-bonding, which is attributable to the low tensile strength of the concrete cover, takes place at a stress level much less than the ultimate tensile strength of the FRPs. To overcome this shortcoming, the deep embedment (DE) FRP strengthening technique was developed for concrete shear strengthening.

For the first time, this project will explore the application of the DE technique for strengthening shear-deficient RC BC joints. Carbon FRP (CFRP) and steel bars will used as embedded strengthening systems. Using both physical testing and nonlinear finite element modelling, the structural response of unstrengthened and DE-strengthened RC BC joints will be examined. An analytical model for calculating the shear strength of DE-strengthened RC BC joints will also be developed. 

• PhD Student: Joanne Leach
• Supervisors: Prof Chris Rogers & Dr Dexter Hunt 
• Duration: 2012-2018

Recent years have seen increasing public, private and policy interest in the performance of cities, especially with regard to sustainability, climate change, resilience and, more recently, liveability.  This has mirrored the increased attention being paid to cities more generally as engines of change and sites of economic and population growth.  In order for cities to move towards increased liveability, it is important first to understand how cities function and how well they perform. This provides a baseline against which to identify and prioritise aspects that would benefit from change and assess the impact of any proposed interventions.  Gaps in performance can then be identified, barriers to achieving a liveable future elucidated, and robust interventions designed and assessed. City performance refers to how well or poorly a city is functioning when set against defined criteria (e.g., sustainability, resilience, liveability).  The assessment of a city’s performance is inherently influenced by how performance criteria are conceptualised and how they are measured.  In order for the performance data to be useful, a determination of what constitutes ‘good’ performance must be made.  Who does this, and how, materially influences the conclusions drawn.  As such, the transparency of this information is crucial for policy making.  Current city performance assessments are many and vary in criteria, measurement methodology, robustness, transparency and applicability to specific urban contexts, with no single method dominating.  This presents a challenge to policy makers and others wishing to use these methods to inform policy.

This PhD programme is developing a City Analysis Methodology (CAM) specifically designed to aid UK policy makers by taking account of a uniquely broad set of perspectives (liveability).  It proposes a new, relational conceptual framework for measuring the performance of cities as well as delivering unique insights into the performance of Birmingham, Lancaster and Southampton.  The research forms part of Liveable Cities, a 5-year research programme exploring pathways to low-carbon, resource-secure cities in which societal wellbeing is prioritised, while changes in population, demography, climate, security of energy / other resources, and a plethora of historical legacies, provide the context (see www.liveablecities.org.uk).

• PhD Student: Khalid Dahmash 
• Supervisors: Prof Chris Rogers & Prof David Chapman
• Duration: 2016-2019

There is current a global boom in construction allied to the growth in the world’s population.  With more than 50% of the global population living in the cities, and the proportion expected to increase to 70% by 2050, the need for infrastructure is escalating.  Going underground is considered to be a future ‘sustainable solution’ in urban areas.  However, going underground is potentially dangerous.  A lack of essential information (e.g. geotechnical and geological surveying data) allied to poor management of information on the underground is one of the basic reasons underlying construction risk, uncertain and often large costs, and not infrequently accidents.  Building Information Modelling (BIM) systems provide a suggested solution to manage all subsurface information and help make explicit and visualise different types of risk.  

The aim of this research project is to develop a Subsurface Building Information Modelling system to manage all relevant information during planning, designing, building and operating underground projects associated with buried infrastructure.  Importantly, tracking subsurface information during building and updating the Subsurface BIM will enable visualisation of the data by each member of the project team to avoid conflicts. 

• PhD Student: Manjola Caro
• Supervisors: Dr Samir Dirar & Dr Andrew Quinn
• Duration: 2013-2017

With increasing numbers of strength-deficient concrete infrastructure; strengthening and repair of concrete structures, particularly in shear to avoid catastrophic brittle collapse, is becoming an issue of international importance. The deep embedment (DE) technique is a recently developed shear strengthening method for existing concrete structures. In this method, vertical holes are drilled upwards from the soffit in the shear spans of existing concrete beams. High viscosity epoxy resin is then injected into the drilled holes and fibre reinforced polymer (FRP) bars are embedded into place. The DE technique provides higher strengthening effectiveness than other FRP systems.

This project examines the bond behaviour of DE glass FRP (GFRP) and carbon FRP (CFRP) bars embedded into concrete. Pull-out tests will be carried out to characterise the bond behaviour and develop a mathematical model for the bond strength of DE FRP bars. The experimental results will also be used to numerically model the bond performance of FRP bars embedded in large scale concrete beams. Finally, the experimental and numerical results will be used to develop design guidelines for DE concrete shear strengthening. The outputs of this project will be of direct relevance to a range of stakeholders including infrastructure managers, designers, contractors and FRP manufacturers. 

• PhD Student: Koohyar Faizi
• Supervisors: Dr Asaad Faramarzi, Dr Samir Dirar, Prof David Chapman

Suction caisson foundation is an upturned bucket of cylindrical shape made from steel, open at the end and closed at the top. The simple installation and easy removal process, plus the low costs of materials and installation procedure are among some of the advantages of suction caisson compared with conventional solutions such as mono-piles. In general, the cost of installation for the foundation of offshore wind turbines can be up to 40% of the total installation cost; suction caissons can significantly reduce this figure since their installation only requires a pump! This has made suction caissons a promising attractive option for use in offshore wind turbine. Despite many advantageous, these types of foundations have not yet been adopted for foundations of offshore wind turbines.

This multidisciplinary research project will look at geotechnical, structural and fluid aspects of the problem to explore installation, bearing capacity and long-term functioning of suction caissons under various, yet realistic, loading and environmental conditions. The problem will be investigated by means of numerical, experimental and analytical approaches to analyse and predict both short-term and long-term behaviour of caissons under the effect of complex loading, and soil-structure interaction during their service life. The result of this project is expected to determine the suitability of using suction caissons as a foundation for wind turbines.

• PhD student: Rachel Fisher
• Supervisors: Dr Andrew Quinn and Dr David Jaroszweski
• Duration: 2015-2020

Great Britain’s railways are considered to be a resilient transport network compared to other modes, however over the eight years preceding the winter of 2013/14, weather and seasonal events on average could be attributed as the cause of 12% of delays on the railways. Railways are subject to a multitude of weather hazards and continuing operation is crucial to the socioeconomic performance of the country thus the aim of this project is to develop a methodological approach to assess the vulnerability of physical infrastructure assets to the effects of weather, both now and in the future by incorporating deterministic and probabilistic methods.

• PhD student: Michael Mammo
• Supervisors: Prof Miles Tight & Dr Andrew Quinn 
• Duration: 2015-2019

The UK's 'Dieselisation' of vehicle fleet in recent years has been an enormous challenge. By 2014, there were 10.7 million diesel cars, representing 36% of the total road fleet, in contrast to only 1.6 million in 1994 (DfT, 2015). Failure to control the growth of diesel fleet on the road has resulted in UK failing to meet the values for NOx set out in the EU Ambient Air Quality Directive in many cities.

To counter this challenge, the City of London is planning to introduce a stringent emissions charging scheme (ULEZ) in the city centre by 2019. Birmingham has also been mandated by DEFRA to introduce a Clean Air Zone (CAZ) Scheme by 2020.

The main objective of the present research is to gain an understanding of how car owners in Birmingham and London would make vehicle replacement and journey-specific decisions when faced with emissions charges. A stated preference survey data will be used to study the trade-offs that car owners make between a range of vehicle attributes, emission charges and incentives when making car replacement decisions, and how these choices are influenced by their socio-economic backgrounds and environmental attitudes. 

• PhD student: Isimenmen Obazele
• Supervisors: Prof Chris Baker & Dr Andrew Quinn 
• Duration: 2014-2018

Climate change has resulted in the increase of extreme weather conditions. Inclement weather conditions induce negative effects on transportation capacity, speed, safety and infrastructure resilience. Both mitigation and adaptation strategies are currently being adopted to curb these impacts. Such strategies include improving drainage systems and attempting to reduce carbon concentrate in the atmosphere through various programs such as afforestation and promoting the use of renewable energy.

This project aims to predict the resilience of sections of the UK’s motorway network to future weather conditions (precipitation and temperature).

• PhD Student: Nikolaos Kalyviotis
• Supervisors: Prof Chris Rogers & Prof Miles Tight 
• Duration: 2015-2018

There is an ongoing debate about the value of the benefits of infrastructure systems (specifically those of energy, water, transport, waste, and communications) and how to prioritize infrastructure investments to encompass considerations of social, economic and environmental wellbeing.  The use of the term ‘infrastructure system’ is related to interdependencies.  

The infrastructure systems that operate in countries and cities are interrelated in different ways, but all have a strong relationship to ‘transport’ – there is a cost and a utility associated with movement.  Infrastructure systems are ultimately created to serve individuals, who place a value on them.  In order to explore all forms of investment and value realisation – what is commonly termed a business model – the relationship between an individual and the transport systems needs to be established.  

The hypothesis being tested in this research is that it is possible to identify both the full range of value created and investments required, and hence to establish a robust business model, for transport systems.

• PhD Student: Stylianos Providakis
• Supervisors: Prof Chris Rogers & Prof David Chapman
• Duration: 2016-2019

Nowadays, most of the human population lives in cities and most of our everyday lives lie within their environments and interconnections.  Moreover, these cities are expanding and as a result their design and planning is important for their future.  Sustainability and resilience, two major contributors for urban liveability, owe much to the urban geological characteristics and processes of the cities’ underground.  That is, they are dependent both on the resources of the subsurface and the geo-hazards that they present – important factors for the future of cities that can provide sustainability and safety, respectively, avoiding costs in the long term. 

This research project utilizes the geological data derived from various urban ground investigations in order to develop 3D Geological Models.  It also combines Building Information Modelling technology, extended in this case to the ground beneath cities, in order to explore the relative physical or manmade effects that occur in the underground.  These effects change the geotechnical and other geo-environmentally related properties with time after construction of city developments occurs.  The aim is to provide a multi-objective tool to determine the geo-environmental impact on future land use planning that is of relevance in selecting suitable sites for development and bringing about sustainable urban design.

• PhD student: Valeria De Laurentiis
• Supervisors: Prof Chris Rogers & Dr Dexter Hunt
• Duration: 2014-2017

Food systems are responsible for around 24% of global greenhouse gas emissions and irrigation accounts for 70% of fresh water withdrawals.  But not all types of food have the same environmental impact.  This research focuses on the importance of dietary choices in a shift towards low impact life styles.  In particular it looks at the school catering sector, and how to assess the environmental performance of school meals.  To this end, a tool is being created to evaluate the carbon and water footprints of a variety of school meal recipes based on the methodology of Life Cycle Assessment. 

This research demonstrates that obtaining low carbon, resource efficient food systems is not only a responsibility of the agri-food sector, but can also be achieved through promoting behavioural change.  It also highlights the role of the public sector in promoting such a twofold shift: on one side using its purchasing power to influence the private sector towards sustainable practices, and on the other setting a good example for consumers and citizens (and in this case students), and therefore operating as a driver of change.

PhD student: Jonathan Ward

Supervisors: Prof Chris Rogers, Prof Miles Tight, Prof Jon Sadler & Dr Dexter Hunt

Duration: 2015-2018

In order to plan for future cities we should start by questioning human experience and systemic relations with the urban environment, as people are the heart and purpose of cities.  We must ask what is a citizen, and indeed what makes a human a citizen in terms of their relations and interactions?  Current approaches to describing and modelling social beings are often unable to properly reconcile sociality and relations with so-called 'hard systems'.  

This thesis will seek to provide explanations of emergent behaviour from an individual and societal perspective.  This requires that we treat society and social actions (or beings) as real and knowable.  Critical Realism’s inherent ability to consider wholly the natural and social sciences, differentiate in the generality of findings, and to look for rules to describe behaviour, offers an opportunity to treat this subject in a new manner.  Using Critical Realism as a lens leads to an explanatory study of underlying mechanisms and structures that shape how we move from beings to actors and citizens through our use of objects, relationships and interactions in particular places.

Focussing enquiry upon the citizen could assist our understanding of how infrastructure and new technologies will mediate their relations with the physical, social and natural world around them.  If we can understand that, we can inform the thinking and design behind the Future and Smart Cities discourse.  We can then begin to understand the possible directions of travel of society and citizen behaviour given certain conditions and emerging technologies.  The thesis will seek to (re)define the relationship between citizens and cities in a more emergent manner, and the definition of what it means to be human in a networked age.

• PhD student: Marianna Cavada
• Supervisors: Prof Chris Rogers & Dr Dexter Hunt 
• Duration: 2014-2017

Cities are fast becoming metropolises that concentrate increasing human activity, creating opportunities as much as challenges in their own context.  Cities respond in different ways to the challenges that they face in current and future city living, notable amongst them climate change, population growth and demographic change, with many expecting technology to help via a ‘Smart Cities’ approach.  However, the Smart Cities concept is not clearly defined – as this research has demonstrated by uncovering 125 different definitions – and can result in confused measures; there is no internationally accepted definition. Often ‘Smart’ is applied to a service that adopts technological solutions and is provided by private organisations, which as a result of its underlying thinking and development can compromise the benefit of the receivers.  

The aim of this research is, through the scientific method, to set the parameters of what we mean by Smart, and understand how cities become Smart and how Smart can be assessed, in order to re-define smartness.  The objectives of this research are being fulfilled through both theoretical and empirical research approaches, using a three-way methodology of database, qualitative and quantitative methods.  The results are being analysed in thematic and statistical models to develop a Smart framework, which is in turn being developed into the SMART model.  SMART is a novel accessible method to assess Smart cities in a transparent and resilient way to leverage smartness.  It is being applied in a case study of Birmingham to explore how to make it Smarter and the findings will inform its incorporation in future envisioning of Smart Cities.

• PhD student: Can Biyik
• Supervisors: Prof Miles Tight & Dr Michael Burrow
• Duration: 2013-2017

Major Turkish cities and urban areas are growing rapidly and as a result are experiencing major impacts from the growth in use of motor vehicles. There are high immigration rates to the cities, relatively weak infrastructure and growing environmental and health problems arising from the growing dependence on the motor car. The research is exploring how Turkish areas might start to reduce their dependence upon motor vehicles and move towards a transportation system based more fully around walking and cycling.

The research has involved the development of visions for the next 20 years in a number of Turkish cities along with narrative and visual aids to support those visions. The researcher has worked with experts and transport practitioners across 5 Turkish cities to explore how they might respond to such futures and to further develop the visions. The final part of the work has involved discussions with the public about the acceptability of the different future visions and their implications on future lifestyle and behaviour.

• PhD student: Carlo Liui
• Supervisors: Prof Miles Tight & Dr Michael Burrow
• Duration: 2014-2018

This research is investigating how urban transport systems can be made to better meet the needs of an older population. Gerontological research is putting increasing focus on the role that mobility plays in later life. Analysis of studies investigating the relationship between ageing and mobility reveals that these are generally characterised by relying only on realised mobility. However, very little has been investigated so far in terms of unrealised mobility, and often with different approaches and results.

Through an intensive review of approaches existing in the literature, this study develops a theoretical framework to investigate which mobility needs remain unfulfilled. It first assesses the concept of mobility needs in later life. This concept is then used to evaluate the best method to investigate factors and barriers leading to unmet travel needs. Five main domains were finally identified necessary to be considered: experience and attitude towards mobility; built environment, well-being and quality of life, health conditions and socio-demographic background characteristics. These will be further explored through interviews with older people in Birmingham, in part drawn from the Birmingham Elders project.

• PhD Student Duy Phan
• Supervisors: Prof Lee Chapman & Prof Miles Tight
• Duration: 2013-2017

This research seeks to examine the resilience of transport systems in mega coastal cities in SE Asia to flooding. The work is focusing on a main case study of Ho Chi Minh City in Vietnam. The work has initially focused on exploring the vulnerability of Ho Chi Minh City to flooding and the relationship between this and current and historical development policies in the city.

The next stages will examine in detail the transportation infrastructure in the city to determine how resilient this is to different kinds of flooding events. GIS techniques are being used to help to understand the geographical aspects of vulnerability of the transport infrastructure to flood events. The work will consider how this vulnerability might change according to different future development policies for the city.

• PhD Student: Sameeh Alharthy
• Supervisors: Prof Miles Tight & Dr Michael Burrow
• Duration: 2014-2018

The aim of this study is to improve the level of understanding on the impacts of features of the transportation service and urban form on walkability in the vicinity of public transport, specifically suburban train stations. The research is developing a model of which are the critical aspects which affect walkability of the urban environment and how these factors might be enhanced in the close vicinity of public transport facilities.

The work is considering both macro and micro aspects of the built environment. To date it has involved a GIS based analysis of a number of suburban rail stations and their vicinity in Birmingham using publicly available sources of information such as use of the stations, service level of trains, density and characteristics of population and quality and type of infrastructure. The next stages will involve a detailed exploration of the local environments at a smaller sample of stations to attempt to understand more about how the micro characteristics of the lo0cal environments could be improved.

• PhD student: Dennis van Soest
• Supervisors: Prof Miles Tight & Prof Chris Rogers
• Duration: 2016-2020

There is evidence that a substantial proportion of walk trips in urban areas take place at each end of other main mode trips (for example walking to the bus stop) and these are often ‘hidden’ if the data collection method does not distinguish each trip stage. Whilst there are often walk stages at the start and end of car trips and sometimes cycle trips, the largest number (and greatest distance) is associated with public transport. Hence, public transport is a generator of walk stages and good well-used public transport systems can be shown to contribute to walking levels and encourage more active and healthy transport. 

This research project would explore this relationship in more detail across a number of case study urban areas and also seek to explore how variable the information on walking is across different places. It would seek to understand if there are constraints or limits to the amount of walking associated with public transport trips and therefore if there are implications for ideal city form/design and public transport coverage/type to promote healthier transport options.

• PhD Student: Giulio Vita
• Supervisors: Dr Hassan Hemida & Prof Lambis Baniotopoulos 
• Duration: 2015-2018

In the near future, Urban wind energy could see a massive growth, due to its undeniable advantages. However, the performance of wind turbines under highly turbulent inflow, which can be found within the Urban Boundary Layer, is far from being fully understood. This specially applies to the signature turbulence on the wake of other obstacles which interact. In particular, the role of the length scale of turbulence is challenging. This research investigates, on one hand, the effect of the inflow turbulence on stalled wind turbine aerofoils, which are complex bluff bodies. On the other, the turbulence within the urban environment is tackled, with special reference to the positioning of wind turbines for the optimisation of the harvesting of energy, regarding high-rise building and their roof area. Both experimental (wind tunnel) and numerical (computational fluid dynamics) will be carried on, focusing on the application of Large Eddy Simulation on a series of simplified and detailed models. Turbulent inlet techniques will be also assessed in their practicability in enhancing the usage of numerical methods.

This project will start a constructive discussion on the negligibility of turbulence as a parameter for the calculation of the aerodynamic coefficient, using wind energy and the urban environment as an current and challenging test-case. The research is founded by the European Commission within the Marie Curie ITN project Aeolus4Future, (cfr. www.aeolus4future.eu).

• PhD student: Michaela Gkantou
• Supervisors: Prof Lambis Baniotopoulos, Dr Marios Theofanous & Dr Hassan Hemida
• Duration: 2014-2017

Technological advances in material science and production methods together with the increasing demand for light and sustainable structures introduced high strength steel (HSS) into the construction market over the last decades. HSS’s main benefit is its high yield stress, which potentially leads to smaller cross-section sizes and hence to lighter structures. Even though some important projects have adopted HSS for the primary structural members, the structural response of HSS is not yet fully covered in codes around the world and the applicability of the current specifications to HSS needs to be assessed.

The current project investigates the structural response of HSS under various load configurations, assesses the current design codes and provides relevant design recommendations. Having studied the structural behaviour of HSS members, the possibility of combining HSS structures with the post-tensioning technique, that would allow minimum material consumption by storing energy under increasing preload, is thoroughly investigated, thus pushing further the benefits of HSS as a structural material.

• PhD student: Wasfe Ali
• Supervisors: Prof Lambis Baniotopoulos & Prof Min An
• Duration: 2014-2020

Both the Highways England (previously Highways Agency) and the DfT Business plan highlight the need for better journey time reliability, optimisation of maintenance costs and increase the accuracy of cost prediction. The objective of the research is to maintain the safety and structural integrity of deteriorating structures over the long term. More specifically for existing reinforced concrete structures the levels of risk will be determined by predicting the reduction in strength and reliability with time and identifying the year when the risk becomes critical and unacceptable i.e. calculating an ultimate intervention date.  This date is then used to develop a cost-effective programme of maintenance and repair works such that every structure is repaired in order to maintain the structural integrity at a safe level of risk and before its ‘ultimate’ intervention date is reached.

The research would give the Highways England a strategy to maintain ageing infrastructure more cost effectively by developing a modelling tool to assess optimal time for renewals, to minimise disruption and maximise network availability. With the outcomes of the research Highways England would be able to optimise both time to renewal and maintenance cost and hence minimise disruption and maximise network availability.

• PhD student: Hamed Almutairi
• Supervisors: Prof Lambis Baniotopoulos & Prof Min An
• Duration: 2015-2018

Rapid developments in modern technology have resulted in much improvement in the construction industry. Construction techniques and civil engineering infrastructure have all benefited from scientific advancement, with projects becoming increasingly dynamic and collaborative. However, risk assessment and risk management techniques have not developed at a proportional rate.

This paper looks into why this is the case, using the construction of concrete highway bridges in the United Kingdom as the means of evaluation. We conclude by demonstrating that the introduction of modern construction techniques adds a complexity to construction projects that actually increases the amount of potential hazards. Further, we find that the lack of a unifying, systematic model of risk evaluation in the civil engineering industry is troublesome. The subjectivism is understandable. Individual project managers will have had unique experiences throughout their careers that cause some concerns to be brought to the fore, and others to be less significant. Nonetheless, the risk management practices that are currently employed by practitioners are found to be unsatisfactory. The most essential factor in providing a lasting solution is identified as an objective standard of assessment.

This is supported by the findings of leading academic researchers in the field – whose works are discussed throughout the paper. We combine their theoretical writings and practical studies with our own data to present a model of risk assessment that can be universally adopted. The model is limited (as is the present study) to detailing the operational best practices to be employed in the United Kingdom. Construction procedures and risk management models that are employed in other jurisdictions were not considered, except for the purposes of comparison or providing context.

The risk assessment model presented is based on fuzzy reasoning and fuzzy analytic hierarchy processes (AHPs). In addition, we also present a cost model and recommendations to be employed in order to minimise the potential risk in construction projects.

• PhD student: Hanwen Zhang
• Supervisor: Prof Lambis Baniotopoulos & Prof Jimmy Yang 
• Duration: 2013-2017

Modular construction has been used for years, which is a kind of construction prefabricated off site and easily assembled on site. Cold-formed steel (CFS), with its positive properties such as high strength-to-weight ratio, is commonly utilized in modules. The benefit brought by this kind of structures is prominent. However, problems were also presented. The challenge mainly comes to the connections. Connections generally take substantial part in the expenditures. An easy erection and effective connection method could considerably achieve great cost saving. Off-site cold-formed steel modular structures are organized by thin-walled open section components. The structure behaviour differences are derived from steel material properties, connections and dimensions of members. Considering the high strength material applied in modular structure and more complex loading conditions, it is necessary to investigate connections in cold-formed steel modular building system and find out the most efficient and effective connecting method in this system as well as the reasonable fasteners. Apart from the failure discussion of the connections, this research aims to investigate the post-failure behaviours of connections, regarding to catenary effect and robustness under accident actions.

• PhD student: Mr. Isimenmen Obazele 
• Supervisors: Prof C Baker & Dr A Quinn
• Duration: 2013-2017

It is an observed fact that the effects of weather on road transport speeds and congestion levels can be quite significant, and can take a variety of forms. In the past, these have been investigated through system wide models and broad conclusions reached concerning levels of delay and congestion etc. This project is investigating this issue from the point of view of individual vehicles. A standard car following model of transport flows (PARAMICS) is being developed to include the effect of rainfall, fog, high temperatures etc. on the fundamental parameters of vehicle movement – most importantly acceleration – and the effect of weather on delays and congestion is being investigated through the sum of the effects on individual vehicles. This will be used in a parametric investigation of the effects of weather on road transport, and of the potential effects of climate change.

• PhD student: Mr. Isimenmen Obazele 
• Supervisors: Prof C Baker & Dr H Hemida
• Duration: 2014-2018

When trains pass through tunnels the aerodynamic drag is much increased from the open-air value, pressure waves are created which move up and down the tunnel, which can cause aural discomfort to passengers on the train itself and on other trains. Much work has been carried out in the past to study these phenomena for passenger trains, but relatively little work has been done for freight trains. This project will use physical modelling techniques (the TRAIN Rig) and CFD techniques to study the aerodynamic effects of high blockage, blunt, freight trains entering a tunnel, in particular the measurement of pressure transients and slipstream velocities.  

• PhD student: Mr. Fahed Salahat
• Supervisors: Dr. P Martinez-Vazquez & Prof Charalampos Baniotopoulos
• Duration: 2017-2020

The project aim is to determine the ductility demand of buildings subject to the combined action of wind and earthquakes. This will lead to the estimation of strength reduction factors associated to those multi-hazard events which can in turn be reflected in design standards. This is of relevance given the fact that strength reduction factors are usually estimated in earthquake prone regions ignoring the contribution of wind.

The key ideas underpinning the proposed research are the facts that wind component is constantly flowing at different intensities and that earthquake events are commonly followed by a number of moderate to strong aftershocks which increase the possibilities of simultaneous load occurrences. 

• PhD student: Mr. Amir Homaioon Ebrahimi
• Supervisors: Dr. P Martinez-Vazquez & Prof Charalampos Baniotopoulos
• Duration: 2015-2018

Progressive collapse is a chain-reaction or spread collapse in which, due to certain causes, a local damage to a relatively small area of the structure occurs, and under certain circumstances, the damage spreads to other parts of the structure and may eventually lead to a total collapse. When the loading pattern or the boundary conditions of a structure changes locally, progressive collapse ensues in structures with overloaded elements and spreads progressively. As a result of the loss of some elements in a locus, the remaining structure has to find alternative paths for the loads previously borne by the now lost elements.

The research will examine this effect on regular and irregular building located in seismic regions subject to different levels of hazard.

• PhD Student: Marek Pýcha
• Supervisors: Dr Michael N. P. Burrow, Dr Gurmel S. Ghataora
• Duration: 2016-2019

A critical aspect of the structural design of railway and road pavements is the non-destructive institute analysis of soil parameters. Similar analyses are required for quality assurance/ quality control during construction and for the appropriate choice of structural maintenance. The Light Weight Deflectometer (LWD) has become increasingly popular for performing such testing due to its simplicity, robustness and low costs per a single test in terms of time and work force. However, the LWD is not yet fully recognized in the majority of road and railway standards because it sometimes produces contradictory results. Recent research suggests that the cause of the contradictions may lie in the mechanical model currently used to evaluate LWD measurements and that a more robust model which can accommodate the dynamic nature of LWD would improve the robustness of the results produced. Preliminary research into the development of such a potential LWD mechanical model has recently been conducted at the University of Birmingham.

The aim of this research is to further refine the newly proposed mechanical model. The research will be focused on two main areas. In the area of numerical modelling, the newly proposed mechanical model, now only uniaxial, will be expanded into multiple dimensions. Also, the governing equations responsible for driving the evolution of the permanent state variable of the model will be further refined to accommodate the full ratcheting and shakedown behaviour.