the engineering and science of decision-making for the transport systems
A WHOLE LIFE CYCLE APPROACH UNDER UNCERTAINTY FOR ECONOMICALLY JUSTIFIABLE BALLASTED RAILWAY TRACK MAINTENANCE
This paper presents for the first time an approach to appraise the investment in railway track maintenance. The approach uses a whole life cycle cost analysis under uncertainty approach which considers the costs and benefits of track maintenance to train operators, users and the environment. The proposed approach is applied to three different route types on the UK main-line railway network to compare a number of alternative maintenance strategies. In all the three cases more economically beneficial strategies were identified in comparison to those currently adopted.
A STRATEGIC DECISION-SUPPORT TOOL FOR THE RISK-INFORMED ASSET MANAGEMENT OF RAILWAY TRACK INFRASTRUCTURE
Railways serve as a key sustainable mode of transportation and there is an increasing demand for railways to expand their capacity, availability and carry goods and passengers at ever-higher speeds. Such increases in usage result in faster railway track degradation rates and higher maintenance costs. Railway track condition, and therefore maintenance strategy, directly impacts track use costs, including train operation, accident, environmental and delay cost. Therefore, maintenance decisions can only be taken responsibly when the costs and benefits of maintenance alternatives are compared on a long-term, whole lifecycle cost basis. To this end, a unique risk-informed decision support tool that uses a Whole Life Cycle Cost Analysis (WLCCA) approach under uncertainty has been developed to take into account the costs and benefits of track maintenance strategies to track maintainers, train operators, users and the environment. The concept of the approach and the resulting decision support tool, known as RITRAK, is summarised in this paper. The RITRAK tool provides strategists and asset managers with an equitable and transparent means of evaluating the economics of railway track maintenance strategies.
A VULNERABILITY-BASED APPROACH TO HUMAN-MOBILITY REDUCTION FOR COUNTERING COVID-19 TRANSMISSION IN LONDON WHILE CONSIDERING LOCAL AIR QUALITY
An ecologic analysis was conducted to explore the correlation between air pollution, and COVID-19 cases and fatality rates in London. The analysis demonstrated a strong correlation (R2 > 0.7) between increment in air pollution and an increase in the risk of COVID-19 transmission within London boroughs. Particularly, strong correlations (R2 > 0.72) between the risk of COVID-19 fatality and nitrogen dioxide and particulate matter pollution concentrations were found. Although this study assumed the same level of air pollution across a particular London borough, it demonstrates the possibility to employ air pollution as an indicator to rapidly identify the city's vulnerable regions. Such an approach can inform the decisions to suspend or reduce the operation of different public transport modes within a city. The methodology and learnings from the study can thus aid in public transport's response to COVID-19 outbreak by adopting different levels of human-mobility reduction strategies based on the vulnerability of a given region.
THE IMPACT OF GOVERNMENT MEASURES AND HUMAN MOBILITY TREND ON COVID-19 RELATED DEATHS IN THE UK
The COVID-19 global pandemic has rapidly expanded, with the UK being one of the countries with the highest number of cases and deaths in proportion to its population. Major clinical and human behavioural measures have been taken by the UK government to control the spread of the pandemic and to support the health system. It remains unclear how exactly human mobility restrictions have affected the virus spread in the UK. This research uses driving, walking and transit real-time data to investigate the impact of government control measures on human mobility reduction, as well as the connection between trends in human-mobility and severe COVID-19 outcomes. Human mobility was observed to gradually decrease as the government was announcing more measures and it stabilized at a scale of around 80% after a lockdown was imposed. The study shows that human-mobility reduction had a significant impact on reducing COVID-19-related deaths, thus providing crucial evidence in support of such government measures.
IMPACT EVALUATION OF ROAD TRANSPORT NETWORKS USING NETWORK THEORY
What are the recent advancements in the technical literature on questions that take into account road transport upgrades in one area causing impacts elsewhere using network theory?
IMPACT OF RURAL ROAD INVESTMENT ON POVERTY REDUCTION AND ECONOMIC DEVELOPMENT
A rapid review of some of the recently published evidence of the impact of such investment in rural roads - the findings of confirm the earlier findings and demonstrate positive impacts associated with increased income, poverty reduction, employment, agricultural output and sales, education, health, traffic volumes, transport services, transport costs and general economic indicators. In a number of the recent studies it was found that rural road investment encouraged structural transformations of villages by facilitating non-farm employment and enabling migration to urban areas. However, this did not necessarily translate into substantial increases in incomes. With increased interest in climate change a small but growing body of literature outlines the potential negative impacts of roads on forest cover and biodiversity, although it depends on the local context and type of road
ROAD SAFETY RESEARCH AND POLICY ENGAGEMENT IN PAKISTAN, NEPAL, TANZANIA
UK's Department for International Development (DFID) invests in research on transport infrastructure to promote knowledge on cross-cutting issues, such as road safety, and to influence standards and practices across the sector. This rapid study provides lessons from DFID funded road safety research and policy engagement in Pakistan, Nepal and Tanzania.
USING WASTE PLASTICS IN ROAD CONSTRUCTION
The idea of using waste plastics in road construction is relatively new. Laboratory tests have shown positive results when a small amount (5-10% by weight) of plastic is incorporated in bituminous mixes (asphalt), resulting in improved pavement stability, strength, and durability. However, international field experience using plastics in actual road construction is quite limited. In this review, we found examples of waste plastics being used in road construction in a few case studies in India, UK, Netherlands, Ghana, Ethiopia and South Africa. While roads constructed using waste plastics have shown good longevity and pavement performance to date, the first roads constructed using this technology are only about ten years old, so long-term outcomes are not yet clear. This review did not find any evidence discussing the maintenance of roads constructed using waste plastics.
RISK MANAGEMENT APPLICATIONS FOR RAILWAYS
Critically reviews current risk management practices in the railway industry to identify suitable models and suggests recommendations for their further improvement and incorporation within the asset management.