Michael J Markow

DECISION ANALYSIS APPLIED TO ROCK TUNNEL EXPLORATION

Abstract Exploration planning is a process of decision making under uncertainty. The decision if and where to explore depends on construction strategies and cost; the selection of construction strategies depends on knowledge of geologic conditions which are not known with certainty before exploration is performed. The proposed application of decision analysis provides a relatively simple approach to the tunnel exploration problem. The existing knowledge of geology, the possible construction strategies and their costs, the reliability and the cost of considered exploration methods are used to establish if and where exploration is beneficial. The resulting hierarchy of locations where exploration is beneficial and the comparison of expected values of exploration for different exploration methods provides the basis for the selection of a particular site and method. Graphical and simple numerical means have been created that make the proposed approach a convenient and fast tool in the hands of the decision maker.

PERFORMANCE-BASED PLANNING AND ASSET MANAGEMENT

Traditional transportation planning identifies and prioritizes investment needs in system facilities and operations over a 20-year period. A performance-based approach to planning focuses on the projected outcomes of potential investments and the degree to which these impacts support stated policies. Interest in performance-based planning has grown in response to changing demands on agencies’ transportation programs resulting from international trade and economic competition, deregulation and modal competition, environmental regulation, and the pluralistic nature of many transportation decision-making processes. Performance-based planning is systematic and analytic, building upon the following components: expressions of policy in terms of quantifiable objectives; explicit measures of system performance; analytic methods to predict the impacts of different types of investments on system performance; decision-support tools to assist in evaluating a range of investments throughout a transportation network; models for periodic system monitoring to track performance measures; and feedback mechanisms to assess performance trends and identify needed adjustments in investment priorities.

A methodology for intercity transportation planning in Egypt

Abstract This paper describes the development of the Egypt Intercity Transportation Model, designed to assess alternative transportation investment, maintenance, operating and pricing policies within Egypt. The Intercity Model encompasses movements of both intercity freight and intercity passengers on highway, railway, and waterways, and predicts transportation system performance, costs, and impacts resulting from different policies that may be specified. The Model incorporates a number of state-of-the-art analytical procedures and features particularly suited to analyzing transportation problems in developing countries, including: (1) An equilibration procedure which provides a simultaneous solution of the generation, distribution, modal split and assignment problems; (2) Interactions among investment, maintenance, operating and pricing policies through the use of simulation models (rather than closed-form functions) to estimate link costs; and (3) Explicit treatment of constraints on availability of transportation services—not only link capacity (congestion), but also fleet capacity and the potential inability of modes to satisfy all of the latent demand.

Current Asset Management Practices Applied to Pavement Markings

While the principles and methods of asset management are often illustrated by pavement and bridge examples, the approach applies to other components of the transportation system as well. The objective of NCHRP Synthesis Topic 37-03 was to identify current U.S. and international practices in asset management for six classes of nonpavement, nonbridge infrastructure assets: traffic signals, signing, lighting, pavement markings, culverts, and sidewalks. Addressed are the studys findings in regard to pavement markings specifically. Several aspects of asset management were reviewed, including approaches to asset maintenance, budgeting methods, ways of measuring asset performance, estimates of asset service life, materials usage, information technology support, and perceived knowledge gaps and research needs. Study findings indicated that while there is basic agreement on the value of pavement markings, variations in agency management practice, site conditions, and estimates of service life for different marking materials make it difficult to build a consistent body of knowledge. Issues surrounding the different types of retroreflec-tometers in use and the reliability and repeatability of their measurements complicate the situation. As a result, key elements of an asset management approach, such as deterioration models for predicting performance and cost, have not yet been developed with wide acceptance and use. Nevertheless, several efforts have been undertaken that may overcome these problems in the future.

Washington State's Highway Capital Construction Programming Process

The Washington State Department of Transportation (WSDOT) has traditionally been a leader in developing and applying a structured highway capital construction programming process. However, in 1990 it became clear that a new, emerging set of policy issues would confront WSDOT and the transportation commission, and changes to the capital programming process would be needed. Key objectives to be met included (a) a strong, clear connection between the programming process and the emerging policy concerns; (b) a strengthened ability to highlight and evaluate key trade-offs in funding projects; and (c) incorporation of greater flexibility and accountability in recommending projects. A study sponsored by the state’s Legislative Transportation Committee in 1991 reviewed the existing process from both a technical and a policy perspective and recommended changes. A revised capital programming process was recommended to achieve the following: (a) a more clearly defined capital program structure; (b) clearer relationship of the programming process to policy goals and objectives; (c) a more flexible process for allocating resources to competing requirements for funds, as well as greater coordination with other agencies and stakeholders; (d) application of rational methods in ranking projects by priority, including the use of benefit-cost measures as appropriate; (e) consideration of the full range of transportation solutions to a problem; and (f) more complete and timely communication of policy objectives, resulting programs and projects, and performance measures. Enabling legislation was enacted in 1993, and WSDOT and the transportation commission have since implemented this new process.