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Risk analysis plays a vital role in controlling and managing cost overruns in complex construction projects, particularly where uncertainty is high. This study attempts to address an important issue of cost overrun that encountered by metropolitan rapid transit projects in relation to the significance of risk involved under high uncertainty.

In order to solve cost overrun problems in metropolitan transit projects and facilitate the decision-makers for effective future budgeting, a cost-risk contingency framework has been designed using fuzzy logic, analytical hierarchy process and Monte Carlo simulation.

Initially, a hierarchical breakdown structure of important complexity-driven risk factors has been conceptualized herein using relative importance index. Later, a proposed cost-risk contingency framework has investigated the expected total construction cost in order to consider the additional budgeted cost required to mitigate the risk consequences for particular project activity. The results of cost-risk analysis imply that poor design issues, an increase in material prices and delays in relocating facilities show higher dependency and increase the risk of cost overrun in metropolitan transit projects.

The findings and implication for project managers could possibly be achieved by assuming the proposed cost-risk contingency framework under high uncertainty of cost found in this research. Furthermore, this procedure may be used by experts from other engineering domains by replacing and considering the complex relationship between complexity-risk factors.

This study contributes to the body of knowledge by providing a practical contingency model to identify and evaluate the additional risk cost required to compute total construction cost for getting stability in future budgeting.

Design and build (D/B) construction methods have gained more importance in recent years for their potential advantages in improving project performance. There are, however, a number of problems that are commonplace in D/B procurement, which, when they interact with each other, can lead to project time and cost overrun problems. The most important among them are design changes, together with communication and coordination lapses among concerned parties. Past research has focused only on the characteristics of the traditional construction, or separate sub‐systems such as different phases or human resource input to projects. An attempt is made in this paper to improve D/B project time and cost performance. A generic system dynamics model is developed that incorporates major sub‐systems and their relationships inherent in D/B constructions projects. It is validated and calibrated for a typical large D/B infrastructure project using time and cost overrun problems experienced in Thailand. Extensive simulations with many policies, individually or in various combinations, show that improvement in time or cost can be made with proper policy combinations that reflect strong interactions between the whole design and build system and can be derived only if these interactions are accounted for. To achieve overall improvement in both time and cost, the combination of full overtime schedule, average material ordering, and fast track construction with moderate crashing of design is most appropriate. If cost is the focus, extending the construction schedule, combined with material ordering based on actual need, and design and build with traditional construction method is the best solution.

The study evaluates the accident-adjusted dynamic efficiency of public bus operators providing bus transportation services in eight major metropolitan cities of India.

The slack-based measure (SBM)–undesirable window analysis approach is used to gauge the dynamic efficiency levels and identify the sources of inefficiency in bus transportation services. This innovative approach integrates the SBM model developed by Tone (2001, 2004) and the window analysis approach of Charnes et al. (1985). The main advantage of this approach is that one can explicitly incorporate the number of accidents in the production technology specification as an undesirable (bad) output and potently handle the issue of the “curse of dimensionality” in a small sample like ours.

The key empirical findings suggest wide variations in average efficiency levels across sample bus operators in metropolitan cities. The Chennai Transport Corporation is observed as the most efficient and consistent bus operator due to its most stable efficiency performance. The results additionally unveil that the role of managerial inefficiency was diminutive, and the scale-related issues were the real cause of sub-optimal or supra-optimal behaviour of sample bus operators in the resource-utilisation process.

There is an urgent requirement for effective policy intercessions to mitigate the sizeable observed inefficiency in the production process and resolve scale-related issues of public bus operators offering transit services in major metropolitan cities of India.

This paper is maybe the first to assess the dynamic efficiency of public bus transit systems in India's major metropolitan cities after treating accidents.

The purpose of this paper is to demonstrate significant problems in the US' development pattern of regional automobile‐dependent sprawl and local growth management and to make suggestions about adopting a regional growth management model that might better provide for more sustainable development of the built environment.

This paper reviews trends in the USA and elsewhere to determine the negative effects of the current system of sprawl and the potential benefits of developing higher‐density urban centers. The paper also looks to models in some US cities and Europe to further analyze potential legal and political issues related to this type of regional sustainable development.

Unsustainable, automobile‐dependent regional sprawl is a result of local zoning, growth management, and parking programs and has negative effects both now and for the future. The result has been more time, money, and resources wasted in automobile transit instead of new planning models that would lead to a more sustainable and less automobile‐dependent future.

A metropolitan sustainable development governing framework for growth management in the twenty‐first century is essential for a sustainable future. This includes higher‐density urban centers, transit‐oriented development centers, and a change in public attitude away from “not in my back yard” thinking.

This paper provides the potential benefits of creating a metropolitan governing framework to identify and regulate “growth areas” in a region. It further demonstrates how linking these areas to regional transit planning will help achieve the development of higher‐density, mixed use, and intensive urban core job/housing areas where people could live, work, shop, and play without the use of the automobile.

The impetus was to assess pluses and minuses of a national mandate with specific paratransit guidelines per “the” 1990 Americans with Disabilities Act (ADA) model. Two European countries were chosen to explore other ways to serve persons with disabilities, not driven by ADA.

This research compared mandates in each area (via a tri-lingual survey) both as related to ADA’s most common practices and the European model of “Persons with Reduced Mobility” (PMRs). After data collection, analysis compared and contrasted ADA and PMR schemes.

Even in California, differences were found among survey sites; for instance, the organization type and mix of services varied greatly, despite a national framework. In Europe, there were more similar approaches among regions where, without a national framework, there was flexible, regional decision-making. In Europe, the national focus is on more regular transit accessibility, maximizing transit use rather than special services.

Five recommendations resulted and apply most directly to California and equally for agencies with or without ADA. The strengths of the PMR approach are transferable to California and the trend among a few California partners to go beyond ADA, while only a local option, reinforces the strength of the PMR solution.

How to improve service and financial performance and enlarge the private sector role are put forward. Existing methods, whether Federal or California-driven, need revisiting to achieve true benefits of coordination.

The history and development of urban transportation sysems in Brazil are reviewed in some detail. Early urban developments were served by rail and relied upon the rail transit systems but this has deteriorated since the 1930s as a result of high urban growth rate. Rail transport has chiefly been replaced by buses and micro‐buses, and latterly by cars but these have compounded rather than improved the situation. Industrialisation in the 1950s had a profound effect as existing networks were unable to cope with rapid urban development and growth. The social implications of transport costs, wasted travel time, the development of slum areas in inner cities, are considered and viewed as a poor reflection on an industrial and urban economy such as Brazil. The conclusion is drawn that the transportation system may ultimately jeopardise the continuity of Brazil′s industrialisation and modernisation.