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2 Identifying the Opportunities The new agenda for infrastructure research and innovation should embrace both individual public works modes and an in- tegrated view of infrastructure. Modal and integrated, or cross cutting, views offer rich opportunities for enhancing the effective ness and efficiency of infrastructure through new applications of science, technology and engineering. Some of these opportunities are truly new, springing from basic research In many field conducted at universities, national laboratories, add in the private sector. Other opportunities may have been considered in the past but are now more attractive ~ the light of new demands, changed economics, and shifting national priorities. While limited time and resources have prevented a complete formulation of a new agenda by this committee, some of the more readily apparent opportunities malce it possible to define the outline for such an agenda. The com~xiittee's suggestion of promising areas for both mo- dal and crosscutting research faD generally into four categories: . maintenance of exiting systems, often neglected ~ discus signs of infrastructure research, which may include moni- toring of performance, detection and repair of failures, and periodic measures taken to avoid failures; 8
9 . enhancement of existing systems, through adoption of new technology or operating rules to improve quality, scope, or efficiency Without a fundamental change ~ how service provided; alternative systems which involve introduction of new con- cepts or technologies to replace existing systerrm; policies =d management procedures that influence deci- sions about how resources are allocated to month, en- hance, or replace public works facilities. IILUST:I~TIVE OPPORTUNITIES FOR MODAI RESEA1ICH ED INNOVATION The scale of our nation's investment ~ infrastructure and our dependence on that investment warrants increased research effort for ad modes of public works. Government spending on public works has increased ~ real terms (i.e., Accounted for mBation) from $60 billion In 1960 to $97 billion In 1984, but has decreased as 8 share of GNP from 3.7 percent to 2.7 percent (Office of Technology A~ment, 1987~. The Retribution of this spending has shifted sharply over the same period from new construction to maintenance of the existing physical plant, and from federal to local government levee. Spending on research, nearer high, has suffered in this shift. Among the thousands of local governments that might benefit from mnovatiom In infrastructure maintenance and enhancement, only the largest can support research. Federal budgets for infra- structure research In the last three yew (19~1987), measured in current doU~, have remained stable or declined (BatteDe Memo- rial Institute, 1986~. Estimates by the Office of Technology AS sessment (1987) suggest that research spending by private sector infrastructure industries is perhaps 0.3 - 0.4 percent of grow rev- enues, led than one-tenth of what ~ spent on research in other sectors of the economy. While the committee decries this gen- eral lack of attention to infrastructure research, it recognizes that resources will always be limited. The committee selected three areas of modal opportunities to illustrate the content envisioned for its proposed agenda for infrastructure reteach: solid waste management, water pollution control, and urban mobility.
JO Solid Waste M~aBem~mt Frontage newspaper reports of a garbage~filled barge sailing from port to port In the Unmet of 1987 highlighted the solid- w~te management crmm faced by many communities (Fortune, 1987~. I.ike some legendary Flying Dutchman, the barge's cap- t~ encountered the wind of public opinion that with mereas~ng force roar "not In my bark yard" to those who search for places to dispose of our mounting of municipal waste. The term NIMBY ho entered the urban planner's ~rocabul~y as shorthand for the public's response to a whole class of land uses that includes ~n- cinerators, resourc~recovery plants, and I,u`~filb designed to deal with solid waste. ~deed, the siting of new facilities has become virtually unpossible In communities across the nation (Paul, 1987~. Within the last decade, the typical cost per ton for solid waste deposal has increased drastically. Some towns on Long Island ship their wastes to Pennsylvania at costs as high as $150 per ton (fortune, 1987~. Environ~r~ental regulations and aging of existing facilities have restricted the options available for waste disposal, forcing closure of municipal incinerators and restrictions on landfill operations. New York City, for example, now uses only two incinerators (both in Brooklyn) of the thirteen in operation before air pollution laws were pawed. Almost half of the city's 26,000 tons of garbage produced dally is sent to the 3,000~acre landfill at Fresh KiDs on Staten ~land, the largest such site In the world. When that site is Fill (which is expected to occur by the year 2000), the mounds of compacted earth "d rubbish wiB be, at 505 It high, the highest Cape south of Ma~ne's Mt. Desert Island on the eastern seaboard (McKibben, 1986~. Where new sites can be found for landfill, concerns for groundwater protection may mandate use of Impermeable lin- ers, clay seals, test wells, and long-term assumption of liability for damages due to leaching of chemical Tom disposed material, thus increasing costs even further. Waste~to-energy and resource- reco~rery facilities-which now handle only about 5 percent of the nation's municipal wastes (Engmeer~g News Recant, 1987) are expected to assume an increasing share of the burden of waste dispose, but they cannot solve aB the problems (Cook, 1985~. There is a temptation to dismiss journal tic reports of im- pending disaster, but the problems of solid waste disposal are truly mountainous. On average, approximately 450,000 tons of
11 waste are produced each day ~ the United States (R.W. Beck and Associates, 1987~. Research and development on solid-waste management ~ stiD In its infancy ~ the United States. It has gained support primarily through programing sponsored since the m-970 by the Environmental Protection Agency. Solid-waste disposal is primarily a local government responsibility, and there me few mechanimnB for pooling interests in innovative technology and policy. The coranaittee feed that more research on solid-waste disposal ~ needed. Beseech ~ needed, for example, to make improvements in known disposal processes, even if the C08tS of Auk improvement may here been deemed us acceptable in the past. We know now that garbage is not "urban ore" that can be mined to make money, and the sale of any wast~generated power, steam, glass, metals, and paper wild only marginally reduce disposal costs borne by municipalities. Neverthele - , there has never been a better time to optimize all aspects of w~t~to-energy and resource-recovery technology and to look for new ways to depose of wastes. Existing systems will not have significant unpact on the problem. Enhancing exiting systems may be achievable and eEective, however. One prosaic but ne~rerthele" probing way to reduce disposal costs ~ to merease public cooperation In separation at the source in order to allow special handling of newspaper, glass, and mets~. Also, there may be ways to reduce the per capita solid-waste burden, such as encouraging less wasteful packaging of consumer products. Another fruity area of research which might help to allay public apprehension, relates to rugged and reliable instrumentation for on-line monitoring of incinerator stack emits signs and stable sensors to monitor soil and water connation. More effective techniques to improve the quality of stack ems-ions by controlling ~rapor~zed metal, dioxin, and suffer dioxide warrant research. Development of fluidized bed combustion with gas tur- bmes, now being successfully demonstrated with coal, may offer improved efficiency and reliability while reducing air pollution emission. In the same vein, adequate treatment of incinerator cooling water prior to discharge warrar ts study. Whether using enhanced or new technology, ~ncmeration and w~t~to-energy conversion produce residual ash. Encapsulation or ~ritrification of incinerator residuals to prevent leaching from
12 landfilLs, once considered ~risiorlary, should now be venously pur- sued, since the remaining life of landfills must be prolonged for the ultunate deposal of these residuals. The rising costs of municipal solid-waste dispose make un- considered or expensi~re innovation in process technology more attractive and ante the wench for alternative systems. Beyond incineration, there is the much more speculative possibility that genetically engineered bacteria can be developed for accelerated biological stabilization of garbage. At present, this is done by com- posting, a process that could become more comanerciaDy attractive if it could be speeded up. Near-term policy research ~ recommended to deal with the previously mentioned public attitude of "not in my back yard." Adoption of innovation in solid waste is already complicated by the obstacle course of local, state, and federal government approval, which even for a demonstrably desirable and weD- engineered project can prolong the tune needed for preliminary approvab to ten years. The near-term appeal of mcmeration and cogeneration options has been somewhat dim~n~hed by the pro- longed controversy over the threat of dioxins in smokestack ems signs and residual ash, a contro~rerey that current public policy and institutional structures have found difficult to resolve. Municipal Wastewater and Water Pollution Control The need to unprove the nation's collection and treatment of wastewater has been recognized for more than two decades, and considerable funds have been expended} in recent years as the United States sought to Thieve a goal of Fish able, swimmable" waters everywhere In the United States ~ the 19~. Indeed, since the passage of Public Law 92~500 (the Clean Water Act) in 1972, approximately $50 billion in federal grant aid has been expended to design, build, upgrade, or expand publicly operated wastewater treatment works, including some collection systerrm (sewers) and interceptors (U.S. Env~ronmental Protection Agency, 1984~. O,rer the same period, private industry spent even more to comply with local, state, and federal environmental protection legmIation. As a result of these expenditures, there has been readily quantified general and continuing unprovement in the quality of the nation's waters.
13 These investments have dealt pnmarily with only one put of the nation's water quality problem urban sanitary sewage. Other issues, equally }mport~t, hare laclted attention. Pollution due to rumor from agricultural lands and livestock feed-Iota, storm cause<] overflows in sewer systems that combine Unitary and stormwater flows, and often exotic toxic and hazardous substances in urban wastewater are, for the most part, not being adequately Alfred by present treatment systems despite the Vestments the nation has made. Further, operation and maintenance of the present systems continue to place heavy burdens on local govermnents ill-prepared to hire and tram appropriate personnel and to raise the revenues to manage these systems properly. There has been increasing recognition that seeking to remove amaD residual amounts of pollutants the last percent of suspended solids (SS) or biochem- ical oxygen demand (BOD) brings a disproportionate increase in costs. This may not be the most cos~effective policy for use of limited resources, except possibly ~ areas where one city may discharge wastewater into another city's source of drinking water, as presently occurs ~ the Missouri ~d ~#iS~ppi Rivers. Cle~ly, new wastewater collection and treatment strategies, technologies, and policies are needed. At the same time, two ,decades of experience have given us a better sense of priorities and underst - ding of our options. Thus, the committee feels this is a particularly propitious tone to undertake a spectrum of research In wastewater treatment. PoDutar~ts are now seen to be more diverse both ~ origin add form than origmaDy contemplated, and reteach may suggest that money spent in achie~riDg the higher degrees of treatment for SS add BOD would yield a greater en- ~rironmental return if it were directed toward dealing with some of the other poDuta~ts. ~ addition, both technology and our un- deratand~ng of how natural systems can assimilate wastewater are mpro~nng. Further improvements through research win yield a higher ferret of water quality for receiving waters as well as signifi cant economic springs. Regears mprove maintenance and management of ex- ~st~ng systems will not only help to protect the nation's heavy investments over the past twenty years in enhanced wastewater treatment facilities, but ~ wiD offer the promise of improved operating performance arid efficiency as wed. Despite the put investments, the Environmental Protection Agency reports that
14 about 30 percent of publicly owned wsstewater treatment plants fail to meet federal effluent criteria. Some of the best opportunities thus may lie In the truing of personnel and the development of effective program for predictive or preventive m~nten~ce. Improvements may be made in existing technology. The con- t~nued development and early demonstration of decade-old ~ran- ar~ts of the conventional activated sludge process would yield signif- icant near-term benefits. These variants, including step aeration, mollified aeration, activated aeration, and short period aeration, can accomplish the same degree of remove as conventional acti- ~rated sludge but with substantially reduced tank volume ant] air supply. Another area for productive research would be the further enhaD cement of the mcreas~ngly credible mathematical modem that have been developed to predict the response of interrelated waterways to pollutant loads of varying strengths at gracious sites. These moclels can help to set investment priorities ~ response to the severity of pollution problems, allocating scarce resources to yield maximum benefits. For the future, we must beam developing alternative systems that come to grips with toxic and hazardous material ~ our wastewater streams and with non-pot source pollution, primar- ily Tom agricultural sources. Some of the techniques, which will require research and development, will address reducing the pol- lutants at the source either by containment or by limiting the use of pollute material. Research to Improve our understanding of these materials' origins, alternatives to these material ~ their primary applications, and means for controlling their diffusion into water bodies is as crucial as research into separation of these pollutants Tom wastewater strew. Specific new technologies for the future could become avail- able, although they are still in the speculative stage. The promise of biotechnology clearly must be considered in a variety of am plications: poison-resistant bacteria for centralized wastewater treatment facilities; organizers capable of digesting, trapping, and in effect neutralizing toxic or otherwise hazardous materials; and, ~ general, biological organ capable of more rapidly, reliably, completely, and cost-effectively neutralizing wastewater contam- enacts Tom both concentrated arid dispersed sources. Similarly, advancement in mechanical separation techniques, such as various forms of filters and ser~iipermeable membranes now available only
15 at the laboratory scale, could become available for wastewater treatment. Perhaps an issue for policy research as weld as for technology development ~ the recognition that wastewater management ~ a regional matter and that regionalization of control must be un- deratood both at the technical and political leered. The goal of research efforts in this area would be to Thieve regions manage ment that deals with the problem at the appropriate scale, tenth the proper controlling authonty and resources, and with the apprm priate understanding of where the most cos~effective Treatments should be made. These investments need not be centralized, as emerging experience with on-site treatment demonstrates (Lom- bardo, 1987~. Also of great import, particularly in older metropolitan meat east of the Misa~ippi, ~ the management of combined storm and Unitary wastewater systems and how to dead with Oreo. Pow sible solutions mclude either mtroduc~g a new separate sanitary system, utilizing on-site pretreatment of water, or using holding tanks to allow the system to catch up with storm-caused surges in demand. They should be equate ~ to costs, reliability and ease of implementation, Siren the potential for Irruption of services in urban environment. Urban Mobility Despite active program of research in highways and, to a much lemer degree in public trait, urban mobility ~ an Yea ~ need of ~nfr~tructure regears and innovation. ~ the sense that the imues of urban mobility bridge several distinct modes of public works, this area may iDustrate cro~cutt~g as well as mode~apecific elements of a research agenda. Regardless of how it is viewed, urban mobility is a pressing problem across the nation. In the I`os Angeles area, for example, time lost by commuters ~ traffic amounted, according to one cs lunate, to 84,000 hours each day in 1986 (U.S. News and W=Id Report, 1987~. 1h high growth suburban areas like Tyson's Cor- ner, near Washington, D.C., the business community as well as residents me concerned that traffic congestion may require dram tic action. They are seeking mnovati~re ways to ease the flow of people and goods (Orski, 1986~. Explosive growth over the past
16 two decades In the work force, priorate vehicles, and suburban em ployment has shifted radically the patterns of Lemma for urban trade Ski, 1987) ~d has far outpaced the transportation m- fiastructure's ability to cope with these demand. The mismatch between growth patterns "d division of responsibility among for cat government jurm~ictiom makes it ~ the more difficult to find solutions to the problem. Past research has shown that solution~may be found in new ways of operating old facilities as well as in designing entirely new facilities. For example, improvements were obtained several years ago at the LincoIn Tunnel In New York City through computerized control of the entrance rate into the tuned. Adaptive metering of the entrance rate, in response to traffic density measurement inside the tunnel, reduced substantially the Chock waVe8n caused by uneven behavior of traffic. This produced an overall secrete In average throughput of ten to twelve percent, enough to eliminate traffic back-ups In most Stances. A number of cities overseas and In the United States, facing the limits of freeway construction, have chosen to focus attention on mug traffic flow on ex~t~g streets. Through central com- puter~zed traffic control, arterial streets can be made to operate like 1imited-acce~s roadways for short period to severe demand or to accommodate emergency conditions. These new systems replace older fixed-mgnal synchronization schemes tenth adaptive control based on traffic demand at appropriate detection points or for particular times of day (Goldstein, 1984~. While the underlying traffic management principles applied are not new, research "d development of software ~d hardware has made it possible to cot ordinate oysters of streets tenth dozens of intersections. Continued research may expand the scale of control to regions. The huncireds of thousand of miles of urban roast streets en d bridges in the U.S. constitute a mature, at able and immensely sig- nific~t element of infrastructure. Size, cow, and integration tenth other parts of the urban fabric argue against dramatic change. Thus, improved maintenance management offers the principal oh portunity for timely and elective innovation. ~ The system's size, geographic distribution, and diversity of condition make inventory control a major challenge to cos~effec- tive management, a challenge that can be dealt with using ~m- pro~red information systems. For example, there are nearly den veloped comprehensive road and street pavement management
17 systems now beginning to be adopted for active use. Although at a more embryonic stage, bridge management systems are also enrolling. These management systems, still susceptible to major improvement through technical research, warrant demonstrations of their effectiveness through application. With such information system, we can for the first time accurately account for the huge inventory of highways, r - a, and bridges in real time, and signif- icantly improve their management. formation exchange among computerized infrastructure data been can minimize the public's frustration with senal rather than concurrent repairs to various infrastructure elements. For example, the repairing of a street, closed first for repair to a water mains then for a gas teal`, and so on, hardly builds support and trust in public errant ar ~ the systems they manage. Materials technology ~ a major U.S. strength, but sophisti- cased eng}neered-materials concepts have not been widely applied to rod, streets, and bridges. While Gongrem has recently au- thor~zed the Strategic Highway Research Program (SHRP), which has allocated $50 million to research ~ this ~es, the committee feed additional effort ~ warranted. Other targets for research and development might include fostering improved inspection Procter cures, more permanent pothole patching materials, en~rironmen- tally safe Id permanent bridge paints or coatings, and lighter, stronger bridge matenals, perhaps utilizing advanced nonmetallic material. The committee believes there are opportunities for enhancing urban mobility through a systems approach combing technic logical, financial, and operational strategies. U=t8 within exiting org~atio=, such as the U.S. Department of Transportation, can senre as foal for enhancing technologies relent to urban mobil- ity. These include both ahs~dn tecbnolog~es" such as data man- agement, tragic 8igDa} electronics, signal system communication, and high occupancy vehicles (HOV)- "d `'~oft" technologies- such as analytical arid simulation modeling, and car and ran pool marketing strategies. Substantial improvements in traffic service quality during per roods of congestion might be achieved through development of alternative systems like Automatic Vehicle Location (AVL). in Such system, individual vehicles are tracked and their drivers are guided through the highway network, depending on the degree of congestion, along various alternate routes to their destinations. ~
18 the most sophisticated dynamo Route Guidance System (RGS), individual vehicles are not just padre targets of a detection gym tem, but communicate their desired destination to the system and receive m~i~ridual ~netn~ctions on a preferred route. A West Germs company reports that it ~ working on such a system. ~ that system, vehicle transponders communicate through relay stations with a central traffic control computer which guides their movement, adjusts the tiring sequences of traffic lights, and diverts traffic from emergency situation. Simi- Iar system "e reported under development ~ Great Bntam and in Japam (Public Duration Abroad, 1986~. In the future, ground-based RGS facilities may be aided by sateDit~based Globe Positioning Systems (GPS). Military am plications of this technology have moored beyond the exploratory stage, providing detection of transponder-equipped objects with a resolution of a few feet. Use of GPS ~ an urban and subur- ban area could augment the capability of grouDd-b~ed systems for rout~gu~dance applications and also provide some additional benefits. A significant alternative system being demonstrated In the United States but actuary berg used elsewhere, ~ automated urban transit, or Automated Gu~deway flit (AGT). Such gym tems have been promoted by developers as offering reduced oper- at~g costs because labor inputs are reduced. Systems operating ~ L.ille, France and In Vancouver, B.C. are cited as demonstrations that the technology, termed by some the Pleading edge" in me tr-sportation, does work (Public l~o~ation Abroad, 1986~. Alternative technology to cars "d trucks ~ not obvious, but limitation in highway technology-including safety, cost, and ~n- creas~g congestion suggest that this area merits thoughtful at- tention to preserve "d enhance our mobility. Research to develop gu~deways to move conventional vehicles, for example, offers the promise of less congestion, greater safety, petroleum earrings, and re<luced pollution. II.[USTPATIVE OPPORTUNITII:S POR CROSSCUTTING 1LESEARCH AND INNOVATION ~ the new agenda for innovation envisioned by the commit tee, research on specific public works modes of the sort illustrated above must be linked tenth broader cro~cutt~g initiatives that
19 take ~ integrated or synoptic view of public works inffastruc- ture. The common materials, construction methods, ~alyBi8 prm cedures, management controb, and policy Sues relent to Al modes offer major opportunities for innovation. They cannot be adequately perceived or effectively captured within the narrow perspective of any single mode. Ill addition, a cro~cutt~g ape promo ~ the best tactic for confronting the barriers that affect aH modes as discussed ~ the next chapter. While many of the opportunities for innovation through crow cutting research spring from adaptations of existing technology to solve specific problem, the committee foresaw that many other opportunities win emerge from reteach of a more speculative nature. Research ~ such broad areas as biotechnology or quantum physics could yield benefits in such unexpected areas as highway maintenance or power generation, benefits that are as likely to be realized in maintenance as id new alternati~re~3 to existing public works systems. To illustrate the opportunities for the cro~cutt~ng facet of its proposed agenda, the committee examined several areas applicable to aB infrastructure modes: material science, information Ethnology, nondestructive evaluation, and urban and regional planning. Materiah Science The building blocks of current infrastructure facilities gen- ersBy comet of 8 few mittens concrete, asphalt, wood, and steel. Over the past several decades there has been a revolution ~ material smences that has only begun to be felt in public works infrastructure. Some here enrolled to new lever of sophistication, and can contribute significantly to public works Theology. They include polymers, game, ceramics, and superalloys; membranes, composites embodying the charactermtics of multiple mittens, and coating; and both advanced factory fabrication and ~n-situ processing techniques. For exarnpb, past research on concrete has led to admixtures that have reduced the amount of water used In concrete mixes, Mewing to much higher strength In the finished matenal tenth no reduction In workability during construction. New structural den signs and reduced mittens usage have followed this innovation (Mindess and Young, 1981~. Other admixtures have aided main- ten~ce by reducing concrete's susceptibility to mat corrosion on
20 northern highways Id ~ waterfront facilities. -Coning ret search on use of lightweight aggregates or metallic or polymeric fibers in the concrete mix may lead to further innovation that could be used for concrete pipelines and in all types of facilities construction. High strengths weight nomr~etaDic woven fibers and posy mer-unpregnated fabrics have already made a major impact ~ architectural applications for sporting facilities and tempor~y-use structures. Application to infrastructure that warrant research include replacements for steel cable USA in suspension bridges and prestre~ concrete structures, and for tunnel liners, pipelines, storage tanks, ~d highway pavement foundatio - . Techniques to recondition or otherwise strengthen and protect materiab Direly in place offer the means to upgrade structural performance ~d increase facilities' service lifetimes. Polymeric sprays that penetrate and harden in place and cortege and lin- ings applied to pipes and structural components offer promising applications of flew technology. ~farmatitm ]?e~olog' The assembly, management, transmission, and analysis of in- formation about infrastructure systems ~ an essential element of infrastructure development and management and therefore, a fer- tile area for research. Computers and telecommunications are the instruments of information technology applied to Structure. The tremendous impact of computers on science u,6 technology as a whole ~ already reflected in infrastructure, but the scope for further impact remains vast. Applications of data collection and management, process control, predictive mo<lehing, and Section support analyses, already cited for particular public works modes, can be found in all areas of infrastructure. Such research should continue. Computerized monitoring of the condition and performance of the f~i~ities is one area of great promise. New bridges can be instrumented, for example, to give continuous information on structural inte~ty (Di Vietro, 1986), and instrumentation could be developed for other applications. Computers wiD collect and analyze the data, alerting facilities managers to the need for cor- rective maintenance. Simply knowing where infrastructure is located and how it
21 is designed will be an innovation In many cities with decades of successive construction and reconstruction (Godfrey, 1985~. Even when such records are available, the task of coordinating volumes of information may await research and development of inexpensive and fast methods of entry, processing, and display of design data. Even if data is lost, computer-based decision systems might be developed to help managers decide where they should look for a failure when service problems occur. Unlike computers, which are clearly tools for use in ~nfrastruc- ture development and management, some observers may argue that the widespread availability and use of common Attribution corridors make telecommunications simply another mode like high- ways and water supply. However, the committee found it difficult to consider infrastructure innovation without discussing telecom- munications as a cros~cutt~g technology. Telecommunications in the United States has never been treated truly as public works. With the effects of deregulation of the telephone industry still evolving, it ~ even lem of a public works mode today. Neverth~ less, rapid development in technology, competition among metallic wire, fiber optics, and the air Warren as transmission media, and the burgeoning range of services associated with telecommunicate tions (e.g., computerized message services and advertising, cellu- lar telephones, interactive video, public access data bases) present tremendous opportunities for research leading to innovation in the more traditional areas of infrastructure. Some opportunities have been mentioned. Uaffic signal gym tems for urban mobility wiB depend on reliable telecommunica- tions to link control at intersection with one another add with the central computer. Route guidance and geo-positioning systems will depend in a very basic way on telecommunications. Nonde- structive evaluation techniques for monitoring structures remotely may use telecomrnunicatiom to collect measurements from sensors. Similar potential uses are arming with other modes. Improved interpersonal communications (through electronic mail as well ~ menage services) can speed the dissemination of information on facilities' conditions ~d new management Procter cures. Research will be needed to determine whether such faster dissemination techniques win have as significant ~ impact on public works infrastructure as ~ other fields. Earlier forecasts that telecommunications might significantly reduce travel have proven incorrect. However, improved video
22 teleconferencing methods may yet prove effective in relieving prom lemm of intercity as wed as mtraurban mobility (Public Innovation Abroad, 1987~. The implications of such technology for future infrastructure needs warrant research attention. NondestrQctne Erahlation Nondestructive evaluation (NDE) refers to a family of pros ~ ~ ~ ~ · ~ · ~ · _~ ~ __1~ cedures employing probing radiation BUCh ~ x-rays, u~tr~on~cs, and radar for performance monitoring and anprov~ng system reli- ability. NDE presently finds limited application In infrastructure areas, primarily in electric power plants and highways. The com- ~ttee formed a pane! to examine NDE in some detail as a partic- ularly promising example of how research could lead to innovative technology that cuts across several public works systems (see box below and the Appendix). Opportunities :fo~ Apron :R.liab~ty of.~blie Worlds Using Nondestructive E - Cation Public works systems are large and comply, }cane long service lives, and acme to them is sometimes difficult (e.g., below-grade utilities lines). As these systems age, facility managers need more effective ways to ~e the capability of their-gems to pros Ride contmoo~ and reliable operation Nondest~ctne Valuation (ND E) can yield key information for this condition ~m~t with- out requiring act~o~~that mint t}~reateD the pyst~n's integrity and continuing~operatio - . NDE was selected by tips committee ~ a ; case stndy of flow oppo!S~itie8 may :he ~dentifieil Ad realized through a new agenda for ~fraetr~cture- relearn. ~ A special pane] of the comm~tt" prepared the report on NDE amen is the Appending Tlie deport conclnd" that Inter n8e of NDE coupled trite stan~rdisati0n Id a failure ~1ysm framework would be a cost~ective ~Nay^to Move the seliab'0ity of public worlds, but that a focused Sear effort is needed to apiece ski" capability. The MDE panel's Erg recommendations mYohre the implementation of ~ near-term demonstration :pro3ect that would both demote she pot~tial.e£ecti~r~n~ of NDE t~iques and Uprose time tedh~uques via applied rcsear~. This near-term demonstration :pro~ect would parolee coordi- nated Se}d testing of Bevel comme~i~ available N1:)E methods to Agate their t:apabilities~to provide reliable {acili$ r condition "formation. airbill utility corritore in city streets appear to be the most attractive ca;ndidatc for ibis effort, t}~ongh others in- clodc dams (and pa - ;~ aquifers), piping Aster, large pumps for wastewater treatment, and bridge str~ctu~.
23 The city street-utility comdor represents a complex "fray tincture example which may include (a) street pa~remeDt, (b] gas utility lines, (c) sewer lince, (d) water lines, (e) electric lmes, (f) telephone lines, (g) steam lines, and (h) special communication lines. Individual agencies or these facilities Ed share the com- mon nadergro~d..epace. The actions of ear}` sgcacy c" affect the others, creating a collective need to effectively manage the dergro~d space. Institutional, financial, and technical barriers restrict the Bow of facility condition information Song she facility opera. The city street-nti}it~r corridor ~ ~ ~rorthwl~ile case not only becanse~of its importance to.ntility operatio:", but also became indnridnal m~icipaliti" ~1b do not here the financial} resources to concoct such an mraluation alone. S - oral study sites should be selected for condition amassment, resecting a diversity of gem graphical, construction, materials, and ~reather~related {actors to ensure that the study r - nits arc rep~entatwe of condition across the U.S. The demonstration project should be d - - ed to meet the following study objectives: Provide field level information on the capability of al- ternative commercial and emerging NDE te~iqu" to determine accurately the conation.of fic'diti - ; Develop .procedor" for the comparative ~ah~ation of NDE technique for iev~oatK,~ of "f~tr~ctorc facility; · Compare the accuracy of t}~ altemative commercially available NI)E technique tenth current practice; Compare the results of alternative NDE te - piques on t}~e · same str~cture(~; - Assess the fea8ibilibr of Meg mc~t~g.NDE ted to define facility condition. .. . . . . The project should ~ structural by a project m~r~ty~ation teen tenth expertise both .m public words inspection . and in NDE. The team would have to "tabling enteria for ~ch factors as NDE methods to be chided ~ the cam stud Ed tost protocols :It ~ anticipated that broad participation ~ t}~e studier by.ad~rocates of Canon ta~niq~es would he d~irab~, as would wide spomor~ip or ~doreemcat by . Iterate Tile consortia. All information Generated would be made Salable to the public. One of the most far-res~rhing opportunities for employing NDE research ~ In the evaluation of concrete material. Concrete, as already noted, appears In a wide variety of infrmtructure appli- cations such as highways, buildings, and piping for water and wastewater. In Al these uses, flaws ~ the concrete c.~., air pock- ets, cracks, corrosion-can be serious problems. Recent research
24 on flaw detection that combines acoustic methods, digital signal processing, and computer-based analysis has led to the unpact- echo, ~tre~wave propagation technique, which is capable of iden- tifying certain internal interfaces such as cracks, grouting joints, and groins in concrete. The reliability of this technology needs more evaluation. Development of field test systems is also needed. Permeability is the most important characteristic for con- crete's long-term performance, because this affects the rate of infiltration of such undesirable elements as chloride ions, which in turn affects corrosion of the reinforcing bars or wires in high- ways, bridges add pipes. NDE methods are needed for ~n-situ measurement of permeability. Assessing the condition of tendons In pos~tensioned precast concrete elements warrants research. NDE methods should be sought which determine whether tendons are protected by grout- ing or have undergone some corrosion. New NDE methods for con- dition assessments of roadways are needed to provide Formation on the subgrade as weD as the pavement. For new construction, sensors should be developed that can be embedded in the struc- ture to allow continuous monitoring of structural conditions. Also dunng new construction, NDE should be developed to monitor the compliance of construction with accepted standards and contract specifications. More rugged, user-friendly, portable, ard inexpensive field equipment ~ required for virtually all NDE applications. Research is needed in all applications to establish limitations as well as capabilities of NDE procedures. Urban and Regional planning AB infrastructure systems have evolved, patterm of human settlement and economic activity have shifted to take a<~,rantage of new opportunities to use resources and to overcome constraints of distance, Isck of reliable water supplies, or shortages of fuel. In turn, inability to fashion infrastructure systems to meet the demands of these shifting patterns has demonstrated ~ need for new ways to manage urban add regional development. Viewed at the regional scale, maintenance and management Of individual public works modes often depend on maintaining a balance with other modes. An example is the Bow of water fro supply systems into wastewater treatment systems and eventually
25 back into water supplies. E the quantity of water used or the amounts of poDut~nts introduced during use are reduced, then the demands for treatment and deposal also win be reduced. Research to develop improved regional mon~tor~g of water use could yield benefits ~ wastewater management And reduced costs of water supply and sewer networks. The concept of utilidore, common underground tunnels to serve several utilities, evolved as an enhancement of the present system of separately locating various water, wastewater, sad other utility lines under urban streets. Because Aced to the interior of a common and physically larger utilidor would be relatively led disruptive and expensive than repeated excavation of streets, the concept has the potential for increasing flexibility to accommodate changing technologies (e.g., conversion from copper to fiber-optic cable) and for consolidating other utility services (e.g., telephone and electricity) that in many areas are provided above ground. Utilidors, by providing a means for deli~renng multiple infract structure services, necessarily involve multiple institutions. Mak- ing this technology a practical reality will require a combination of technological "d policy research, the latter to facilitate the co-Iocation of ~nfrmtructure elements owned and operated by a variety of public and pnvate service providers. Technological ret search must address corers system design i - ues to constrain o~rer- all costs, allow access for utility system maintenance, provide for future maintenance of the utilidor itself, accommodate unantici- pated technology innovation, "sure a high ferret of reliability, Ad minimize the potential for common-mode failure. Policy research issues mclude the determination of the type of enterprise needed to construct and operate the system, how it might be financed, and what services are best provided in this manner. Jurisdictions concems are not restricted to the utilidor con- cept, but are in fact basic to effective infrastructure development and management. Regears ~ needed to find new ways to a - let local electorates to comprehend the often obscure unplications of regional issues of capital spending and system management. New ways for governments at ad levee to communicate and cooperate ~ timely and effective mater are needed as well. F~nanc~g ~nsti- tutions (e.g., regional infrastructure baked, systems for allocating and controlling liability in the face of escalating court award, the roles of go~remment and professional bodies in setting development standards, and the unplications of such concerns for adoption of
26 technological innovation ~1 are potentiaDy fertile relearn areas tenth cross cutting applications. Over the long term, research may lead to more efficient paw terns of urban development. While such ~rmionary megastruc- tures as Solen's "archologies" or Compact cities (Danzig and Sasty, 1973) may not soon append on the Amenc~ landscape, the widespread use of clustering in suburban housing development, innovation of the 1960s and 1970s, could evolve into demer ur- ban clusters in the future. Research into demographic trends and methods for delivery of urban services may have profound impact on tomorrow's infrastructure. CONCIUSIONS A irarnework ho been propose for a new research agenda to foster infrastructure innovation. To illustrate the opportunities contained within such ~ agenda, examples have been given of both mode-specific and crosscutting research projects of the type the committee feed are appropriate elements of such a new agenda. The examples presented here are just that-the committee's suggestion of topics that warrant inclusion ~ projects ~ ~ Afro structure regears agenda. Development of a comprehensive and balanced wfr~tructure research program requires more time "d resources than was available to this committee. More importantly, the professions and user communities should be drawn into the process of creating this agenda.