4
ANALYSIS AND DECISION TOOLS

With the introduction of new materials, improved measurement abilities, and expanding environmental concerns, infrastructure professionals find their old analysis methods, planning and design tools, and rules-of-thumb no longer adequate for decision making. Research is needed to develop better tools for assessing the service behavior of infrastructure components, the interactions among components, service problems that may be encountered, and their solutions.

Improved methods for forecasting need, regulatory changes, and societal demands, for assessing impact and risks associated with new and innovative practices, and for modeling system behavior will provide rational, documentable analysis and will support policy decisions. Payoffs will include improved ability to incorporate nontechnical, societal requirements, issues; and benefits into infrastructure planning, design, and operations decision making.

Repair and upgrading decisions are often poorly integrated with either long-term planning or day-to-day management. Constrained resources for planning and condition assessment of physical systems too often do not allow timely, cost-effective decisions regarding infrastructure repair or rehabilitation. Allowing infrastructure systems to deteriorate to the point that replacement becomes the only viable option is simply no longer acceptable. Separation of construction and operations responsibilities among different agencies often aggravates this problem. Research to support operational tools for condition assessment and maintenance management will facilitate planning of systems repair, rehabilitation, or upgrading.

The committee proposes that the NSF should foster research to develop analysis, planning, and design tools that will support integrated infra-



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Toward Infrastructure Improvement: An Agenda for Research 4 ANALYSIS AND DECISION TOOLS With the introduction of new materials, improved measurement abilities, and expanding environmental concerns, infrastructure professionals find their old analysis methods, planning and design tools, and rules-of-thumb no longer adequate for decision making. Research is needed to develop better tools for assessing the service behavior of infrastructure components, the interactions among components, service problems that may be encountered, and their solutions. Improved methods for forecasting need, regulatory changes, and societal demands, for assessing impact and risks associated with new and innovative practices, and for modeling system behavior will provide rational, documentable analysis and will support policy decisions. Payoffs will include improved ability to incorporate nontechnical, societal requirements, issues; and benefits into infrastructure planning, design, and operations decision making. Repair and upgrading decisions are often poorly integrated with either long-term planning or day-to-day management. Constrained resources for planning and condition assessment of physical systems too often do not allow timely, cost-effective decisions regarding infrastructure repair or rehabilitation. Allowing infrastructure systems to deteriorate to the point that replacement becomes the only viable option is simply no longer acceptable. Separation of construction and operations responsibilities among different agencies often aggravates this problem. Research to support operational tools for condition assessment and maintenance management will facilitate planning of systems repair, rehabilitation, or upgrading. The committee proposes that the NSF should foster research to develop analysis, planning, and design tools that will support integrated infra-

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Toward Infrastructure Improvement: An Agenda for Research structure management. These tools, in many cases applied by professionals operating in areas not well covered by traditional educational programs, must bridge among disciplines. Three major research areas that offer high payoff potential are discussed in this chapter: development of systems models that planners, designers, and managers can use to consider the interactions of infrastructure modes among themselves, with their service environment, and with changing user demands; development of ways to achieve faster integration of new technology into infrastructure design and management practice; and development of improved methods for anticipating consequences of catastrophic events and developing appropriate response strategies. SYSTEMS MODELS Few interactive models of infrastructure system components have been developed that can effectively be employed in planning and design settings. While network models for transportation, water supply, and electrical energy transmission are routinely used in planning, these models have limited abilities to address intermodal interactions or related issues such as environmental quality and multiple use of public facilities. Urban development and operations models that could be used at large scales have poor records for accuracy in relation to their costs, and suggest that improvements may lie in sharply reducing costs rather than increasing complexity. New models of energy delivery systems, for example, would support analysis of the entire process from primary source generation to waste-product disposal. Areas of largest analytical uncertainty include technology improvement forecasts, fuel substitutability, and waste-product disposal, issues that are not easily addressed using most standard analytical tools. In the area of telecommunications, policy analysis methods are needed to support consideration not only of intra-system options but also of linkages among information and data processing. Computers, information management practices, and sensor technology are enabling ''real-time'' monitoring of infrastructure conditions and fast management responses (Chapter 5). Infrastructure professionals need tools to take full advantage of these capabilities for improved responsiveness to demand and mitigation of adverse effects of infrastructure deterioration or failure. Research in this area would deal primarily with development of reliable and cost-effective procedures for forecasting system behaviors and selecting among plan, design, and operating alternatives. Included in this range of research would be efforts to improve methods for demand analysis, particularly with respect to intermodal effects and consequences of uncertainty. Assessment of experience is needed to support modification or replacement of currently used models and methods.

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Toward Infrastructure Improvement: An Agenda for Research Ex Post Analysis Of Planning And Design Methods Research is needed to review and evaluate experience with infrastructure in service versus assumptions and conclusions on which planning and design decisions were based. Remote-sensing technologies and survey collection of socio-economic data may be required to support such research. Case studies could identify critical points in infrastructure decision making and clarify how decision support tools influence outcomes, giving attention to technical and nontechnical (i.e., societal and political) factors. Typical questions for research might include the following examples: How do experiences with siltation at locks and dams compare with design expectations, and are changes in design methods warranted? Can remote-sensing technologies developed for defense and space applications be adapted to infrastructure condition assessment and maintenance management, site assessment, and demand estimation? How has infrastructure usage changed with time in ways that were not anticipated in planning and design (e.g., changing patterns of community development, service needs, and substitutions of new services for older ones)? Can life-cycle models be developed for predicting system performance as a function of design details for those infrastructure modes that lack such tools? Can risk management and environmental pollution-abatement models (particularly for nonpoint sources) be developed to bring concern for these issues into the range of routine planning, design, and operational decision making? Demand/Capacity Analysis Infrastructure elements seldom have a clearly defined capacity limitation. Typically, increasing demand leads to increasing usage and degrades performance, which then inhibits demand. Highway traffic congestion is perhaps the clearest example of this effect, but delays in receiving telephone dial tones, flickering electric lights, and variations of water pressure demonstrate its symptoms in other infrastructure modes. A variety of research is needed to improve understanding of the relationship of demand and capacity, develop new tools for analysis, and explore ways to enhance performance of current systems through demand management. Typical questions for research might include the following examples: Are there practical design alternatives for separating segments of demand (e.g., cars and trucks on highways) and thereby improving overall system performance? Can ways be found to reduce demand through intermediate processing (e.g., separation and reduction of solid wastes, ramp metering of highway access, and improvements in fiber-optic-system repeater-station technology)?

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Toward Infrastructure Improvement: An Agenda for Research Can better models be developed for estimating costs, risks, and reliability effects of setting design and management criteria to meet less-than-peak demands (e.g., post-yield behavior of piping and structural members, queue formation and clearance at toll plazas)? What are the short- and long-term costs and benefits of shifting or suppressing peak demands (e.g., delayed access to health-care facilities and flow control on bridges)? FASTER INTEGRATION OF NEW TECHNOLOGY INTO DESIGN PRACTICE Designers and constructors too often seem to fail to understand the full range of impacts of new technology, and how to effectively incorporate these impacts into practice. New technology represents unknown risks and impacts that may entail uncertain liability. Research is needed to develop design methods and risk assessment criteria that will allow design, construction, operation, and maintenance practices to readily adapt promising innovations. Typical questions for research in this area, which may be related to studies in technology management (Chapter 9), might include the following: Can improved analytical and design methods be developed for polymeric compounds, ceramics, composites, and other new materials that are particularly susceptible to creep, exhibit time-dependent stiffness variations, rely on toughness to resist failure, or otherwise are poorly suited to analysis with traditional tools? Can procedures be developed for rapid estimation of performance limits for new materials, particularly plastics, ceramics, and composites? Are changing societal values and priorities likely to warrant significant changes in building codes and design criteria? Can more effective systems be developed for rapidly disseminating information about new infrastructure technology to decision makers and the public? ANTICIPATING CONSEQUENCES OF CATASTROPHIC EVENTS Recent catastrophic events such as the Loma Prieta and Northridge earthquakes, Hurricane Andrew, and flooding along the Missouri and central Mississippi Rivers can yield valuable information for improving infrastructure design and management practices to respond to rare events and extreme conditions. (See for example, Practical Lessons from the Loma Prieta Earthquake, NRC, 1994.) Liquefaction of sand fills, saturation and weakening of water retaining earthwork, and wind uplift on roofs are among the

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Toward Infrastructure Improvement: An Agenda for Research effects poorly addressed in current design guides. Research is needed to analyze such experience and to develop appropriate analysis tools and design and operating responses to reduce future risks. Research should address ways of assuring reliability of new technologies, such as fiber-optic telecommunication lines, that may be especially sensitive to earthquakes and other catastrophic events. Applications of alternative technologies, such as cellular communications, may be more flexible or resistant to damage but may have higher costs. Construction activities adjacent to infrastructure elements may cause effects similar to catastrophic natural events, and should also be included in such research. Construction Effects On Lifeline Systems Disruptions of some elements of infrastructure—such "lifeline systems" as water and electric power supply to critical facilities like fire stations and hospitals—pose especially important risks to public health and safety. Research is needed to improve infrastructure managers' abilities to avoid and respond to such disruptions, especially those caused by construction effects such as excavation-induced ground movements and blasting vibrations. Typical questions for research might include the following examples: What deformations are likely and what are tolerable in fiber-optic cables and conduits subject to differential ground movement? Can generalized guidelines be developed for the redundancy needed to manage risk in infrastructure networks likely to be exposed to catastrophic service conditions? Are new design procedures needed for retaining structures and man-made fills exposed to earthquake or other catastrophic events? Emergency Infrastructure Operations Procedures When catastrophic events occur, ability to maintain infrastructure services often makes a substantial difference in levels of loss and time to recovery. Research is needed to improve procedures for emergency planning and management for infrastructure systems. Susceptibility to terrorist attack is a factor that may be included in this research topic. Typical questions for research might include the following examples: Do risks of loss from terrorist action against key infrastructure elements (e.g., bridges, tunnels, and reservoirs) warrant retrofit strategies to increase protection or reduce loss? Are current standards for infrastructure emergency performance assuring acceptable levels of risk?

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Toward Infrastructure Improvement: An Agenda for Research 1989 FIRE IN THE MARINA DISTRICT COMPUTER SIMULATION OF SAN FRANCISCO WATER SUPPLY SYSTEM SPECIAL FIRE VEHICLE COMPUTER SIMULATION OF EMERGENCY WATER SUPPLY A computer model of the San Francisco water supply system was developed with support from the National Center for Earthquake Engineering Research and the National Science Foundation. The model, which was implemented at Cornell University, was used to secure public support for system upgrades, including special vehicles which each carry nearly a mile of hosing and above-ground hydrants. The 1989 Loma Prieta earthquake cut all pipeline inflow of water to the Marina District, as predicted by computer simulations. Using the special vehicles, fire was stopped before it could spread to adjacent blocks, thereby saving lives and substantial property loss. Research is needed to improve procedures for emergency planning and management of infrastructure.