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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation CHAPTER TWO Updating the 1989 Geotechnology Report: Where Do We Stand? In 1989, the role of geoengineering in addressing societal needs was documented by the Geotechnical Board of the National Research Council in Geotechnology: Its Impacts on Economic Growth, the Environment, and National Security (NRC, 1989), referred to hereinafter as “the 1989 report.” Societal needs addressed by geotechnology were grouped into seven broad national issues: waste management; infrastructure development and rehabilitation; construction efficiency and innovation; national security; resource discovery and recovery; mitigation of natural hazards; and frontier exploration and development. For each of these seven issues, the 1989 report identified national needs and critical issues and recommended actions for advancing the role of geoengineering (see Table 2.1). Table 2.2 summarizes the committee’s perspective on the current status and critical issues in geoengineering with respect to the seven broad areas where geoengineering contributes to societal needs, as identified in the 1989 report. Included in this table is a list of unresolved issues and opportunities to advance the contributions of geoengineering in
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation TABLE 2.1 Societal Needs Addressed by Geotechnology NATIONAL NEED AND CRITICAL ISSUE (NRC, 1989) RECOMMENDED ACTIONS (NRC, 1989) MAJOR ACCOMPLISHMENTS THROUGH 2004 Waste Management Current processes used to initiate remediation of toxic and hazardous waste problems and permit new disposal facilities are slow, complex, costly, and adversarial. There is an urgent need for rapid, effective, and economical cleanup of waste-contaminated sites. Develop more technically attainable regulatory standards. New standards and regulations are more realistic: EPA’s EMS concept developed. Introduce new waste containment and treatment technologies. Significant advances have been made in waste containment and in situ remediation technologies. Allow technical considerations higher priority than enforcement considerations. Risk-based corrective action has allowed for more realistic site-specific requirements. Change the Remedial Investigation/Feasibility Study process to the observational approach. Monitored natural attenuation represents an application of the observational approach to remediation. Improve instrumentation needed for performance assessment. Automated and remote measuring and monitoring systems have been developed. Improve site characterization. Some advances, but better site characterization is still a critical need.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEED AND CRITICAL ISSUE (NRC, 1989) RECOMMENDED ACTIONS (NRC, 1989) MAJOR ACCOMPLISHMENTS THROUGH 2004 Infrastructure Development and Rehabilitation Meeting the backlogged rehabilitation needs of existing facilities and development of new infrastructure systems requires a coordinated interdisciplinary approach, with geotechnology playing a prominent role. Develop new materials. Geosynthetic materials have been developed for many applications. Develop remote sensing techniques to both locate and characterize existing facilities. Significant advances in GPR, LIDAR, InSAR, and airborne methods. Develop nondisruptive designs for repair and replacement of infrastructure. Trenchless technologies, minimally invasive ground improvement, directional drilling, advanced ground reinforcement technologies now available. Develop geotechnical instrumentation for site characterization and performance assessment. Some advances in instrumentation, but continuing research and development is needed. Better means of communicating the value of instrumentation to project owners are also needed. Develop new and better soil and rock modification techniques. Remains one of the most studied areas, especially grouting methods, deep densification, reinforcement. Renewed interest in admixture stabilization. Provide a technical basis for life-cycle analysis and design. Advances have been made on materials flows and a better understanding of inventory analysis for construction materials. Technologies are well established for life-cycle analysis for metals and other building materials, many completed by groups interested in understanding their own materials as well as for comparative reasons.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEED AND CRITICAL ISSUE (NRC, 1989) RECOMMENDED ACTIONS (NRC, 1989) MAJOR ACCOMPLISHMENTS THROUGH 2004 Construction Efficiency and Innovation There is a continuing need for development of innovative construction equipment and techniques to efficiently attack the geotechnical aspects of construction. Improve our capabilities in site characterization. Little change in practice. Remains a critical need. Develop new contractual procedures for quantification and distribution of project subsurface risks. Probabilistic methods for developing cost estimates and presenting them to public authorities have been adopted by some jurisdictions. Support research on equipment and technology to assist construction managers. New equipment and methods continually introduced, but improvements tend to be incremental. Initiate a system of accountability and rewards to drive investment in research and innovation for new equipment and methods. New project delivery methods, including design-build and build-operate-transfer, provide rewards for innovation, but geoengineers not fully engaged. National Security We must help meet the national security needs of the United States. Develop a more systematic approach to ground shock predictions. Significant progress has been achieved since 2001 in the estimates of nuclear ground shock and of effects on underground structure, through several new efforts involving joint teams of DOD and DOE experts. Provide a pool of trained professionals for the weapons effect community. DOD and DOE teams include both senior and junior investigators and results are being thoroughly documented.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEED AND CRITICAL ISSUE (NRC, 1989) RECOMMENDED ACTIONS (NRC, 1989) MAJOR ACCOMPLISHMENTS THROUGH 2004 Resource Discovery and Recovery Cost-effective approaches to the discovery and recovery of U.S. natural resources are needed. Improve our ability to “see through” Earth. Research continues; incremental advances have been made. Improve our ability to drill through rock. Substantial advances in directional drilling, measuring while drilling, and measurement of drilling parameters have been made in the petroleum industry. Develop rock excavation methods that are faster and less damaging. Adaptation of drilling technology from the petroleum industry to the geotechnical and construction communities is needed. Mitigation of Natural Hazards Technology must be used to more effectively reduce losses, both in lives and in monetary costs, resulting from natural hazards. Promote better land use planning. National and regional hazard maps (liquefaction, flood, landslide) developed; enhancements to zoning laws in some areas. Encourage the use of state-of-the-art technology for design and construction for hazard mitigation. State-of-the-art technologies are being applied, but continuing effort and emphasis is warranted. Incorporate risk assessment in design and mitigation strategies. Reliability analysis becoming an integral part of many projects. Formal risk assessment still rare. Participate in large-scale field research. Seven National Geotechnical Experimentation Sites, NEES initiative are breaking new ground. Promote international exchange of technology and cooperation in research. Numerous international technology exchanges, scanning tours, conferences.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEED AND CRITICAL ISSUE (NRC, 1989) RECOMMENDED ACTIONS (NRC, 1989) MAJOR ACCOMPLISHMENTS THROUGH 2004 Frontier Exploration and Development We must continue to explore and expand polar, deep undersea, lunar, and planetary frontiers. Conduct basic research on seafloor sediments, arctic regions, and extraterrestrial materials. NSF, NASA, USGS, and oil companies are pursuing research in these areas; geoengineers most active in seafloor and arctic regions. Educate the public on technical capabilities and possibilities in these areas. Little progress. Develop courses that address the unique needs of frontier research. Occasional special courses and conferences. NOTE: DOD = Department of Defense; DOE = Department of Energy; EMS = Environmental Management Systems; EPA = Environmental Protection Agency; GPR = ground penetrating radar; InSAR = Interferometric Synthetic Aperture Radar; LIDAR = light detection and ranging; NASA = National Aeronautics and Space Administration; NEES = Network for Earthquake Engineering Simulation; NSF = National Science Foundation; USGS = U.S. Geological Survey.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation TABLE 2.2 Unresolved Issues and New Opportunities for Geoengineering NATIONAL NEEDa 2004 STATUS AND CRITICAL ISSUES UNRESOLVED ISSUES AND NEW OPPORTUNITIES Waste Management and Environmental Protection Status: Many new technologies have been implemented and more are under development. Risk-based corrective action and monitored natural attenuation have provided significant savings in many cases. Significant global environmental problems Formal adoption of the observational method (adaptive management) for site remediation projects Bioengineering methods for in situ remediation and containment barriers Long-term stewardship of waste landfills and contaminated sites Consideration of wastes as “resources out of place” “Cradle to cradle” management of wastes Strategies and technologies for alternatives to landfilling Carbon sequestration Remediation of contaminated sediments Regional databases and data models for environmental data Advanced sensors and remote sensing Urban surface water management; erosion and sediment control Critical Issues: Many challenging sites still need to be remediated. Additional technological development is still needed, including development of appropriate waste containment and remediation technology for developing countries and technology for reduction, reuse, and recycling of waste materials. Cleanup, restoration, and protection of wetlands, rivers, harbors, and other waterways has become an important consideration.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEEDa 2004 STATUS ANDCRITICAL ISSUES UNRESOLVED ISSUES AND NEW OPPORTUNITIES Infrastructure Development and Rehabilitation Status: New materials and technologies have made significant inroads in practice. However, little progress has been made in clearing the backlog of infrastructure needs. Life-cycle cost analyses are more refined and sophisticated, but still not widely embraced for selection of preferred alternatives. Sustainability considerations are becoming more important. More discriminating, penetrating, and cost-effective methods for seeing through the ground Better coordination between planners, designers, constructors, and users Passive methods for ground improvement, including biostabilization Regional databases and data models Smart geosystems and adaptive management methods (using the observational method) Biofilms for corrosion protection Long-term durability of geosynthetic materials Use of formal reliability and life-cycle cost analysis Quantification and reduction of uncertainties Critical Issues: Wider use of life-cycle cost analyses, including incorporation of sustainable development and other social values, improved modeling of environmental impacts of infrastructure development, rehabilitation of existing geofacilities, and enhanced durability of geoconstruction.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEEDa 2004 STATUS AND CRITICAL ISSUES UNRESOLVED ISSUES AND NEW OPPORTUNITIES Construction Efficiency and Innovation Status: New project delivery methods (e.g., design, build) have had an impact on innovation and efficiency. Significant advances have been made with respect to new equipment and techniques for geotechnical construction, particularly with respect to ground improvement. More efficient means of underground construction remains a critical need and improved remains one of the greatest needs in geoengineering. Improved site characterization Remotely controlled, automated earthwork construction Better matching of soil and rock conditions with equipment and methods Use of adaptive management systems for application of the observational method Many aspects of tunneling and underground construction methods, including materials handling, directional methods for site characterization control, excavation, safety, ground support Trenchless technologies More energy- and cost-efficient ground improvement, including biotechnologies Easier handling and better improvement of wet and weak soils Critical Issues: More efficient and economical and less disruptive underground construction and ground improvement, minimizing environmental impacts of construction activities. National Security Status: Homeland security has become a critical national need, and focus has shifted from national to global. New and better methods for hardening sensitive and critical structures and infrastructure Improved methods for threat detection, including detecting and locating underground intrusion and surface traffic Appropriate energy, sanitation, and water technologies for developing countries Development of secure reserves of strategic resources Critical Issues: Providing adequate, appropriate, and reliable civil infrastructure; securing civil infrastructure against internal and external threats; reducing dependence on foreign oil; providing secure sources for strategic natural resources.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEEDa 2004 STATUS AND CRITICAL ISSUES UNRESOLVED ISSUES AND NEW OPPORTUNITIES Resource Discovery and Recovery Status: Sustainability concerns have moved to the forefront for energy and water resources development. More reliable, discriminating, and penetrating methods for seeing into Earth Optimization of energy resources More sustainable resource recovery methods Improved waste and tailings handling and disposal methods Carbon sequestration Groundwater recovery, protection, and recharge Critical Issues: Providing necessary resources for sustainable development and national security and minimizing environmental impacts of resource recovery and use. Mitigation of Natural Hazards Status: National and regional hazard maps (earthquake, flood, and landslide) have been incorporated into zoning laws and land use planning in some areas. Formal geohazards risk assessment is becoming an integral part of some projects. However, many communities are still at risk and continued research is needed. Less complicated and more easily understood risk and reliability assessment methods Remote sensing for hazard forecasting and monitoring Nonintrusive and passive methods for mitigation of geohazard risks to existing structures and facilities, including biotechnologies Land use planning and zoning to account for geohazards and their potential consequences Appropriate technology to mitigate major losses of life and property in the developing world Critical Issues: Improved regional hazard monitoring, forecasting, communication, and land use planning; appropriate hazard mitigation technology for developing countries.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation NATIONAL NEEDa 2004 STATUS AND CRITICAL ISSUES UNRESOLVED ISSUES AND NEW OPPORTUNITIES Frontier Exploration and Development Status: NSF, NASA, USGS, and oil companies are pursuing research in these areas. However, geoengineers are often not involved in these ventures. Fundamental knowledge and understanding New sources of natural resources (long term) New habitats (very long term) Critical Issues: Exploration at the frontiers of the natural universe ultimately leading to new frontiers for natural resource recovery and human habitation. aAs defined by the Geotechnical Board (NRC, 1989). these areas. The unresolved issues and the opportunities to address them are discussed in more detail in subsequent sections of this chapter. The chapter concludes with the committee’s perspective on the major knowledge gaps that need to be closed for geoengineering to realize its potential in addressing these issues and opportunities. 2.1 WASTE MANAGEMENT As one of the least mature areas of geotechnical practice in 1989, it is not surprising that waste management is one of the areas in which substantial progress has been made since that time. The 1989 report identified an urgent need for rapid, effective, and economical cleanup of waste-contaminated sites. While progress has been made, many sites remain to be remediated, particularly large complex sites such as Pit 9 at
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation the effects of natural hazards and disasters. Geoengineering plays essential roles in identifying and describing the destructive forces and effects of extreme events, such as landslides and debris flows, earthquakes, floods, tsunamis, expansive and collapsing soils, volcanoes, and even wildfires. The world saw a direct example of the need for geoengineering to play these roles in the December 26, 2004, tsunami disaster. Geoengineering is important in evaluating the resistance of the natural ground; assessing the risks of loss of life and property; evaluating and choosing among acceptable risk mitigation, emergency response, and disaster recovery alternatives; and the development of hazard and disaster-resistant designs. On average, natural hazards (landslides, avalanches, erosion, subsidence, swelling soils, floods, earthquakes, volcanic eruptions, high winds, and tsunamis) cause numerous casualties (deaths and injuries) and billions of dollars a year in damage (USGS, 1995). Related to these, although not natural hazards per se, are a variety of dam, embankment, and surface impoundment geohazard issues, including seepage, piping, erosion, settlement, and slope stability. These hazards demand greatly improved prediction, prevention, mitigation, and post-event recovery strategies and methods. The 1989 report called for more effective application of technology to reduce losses, both in lives and monetary costs, resulting from natural hazards. Geotechnology has been effectively applied over the past 15 years for natural hazard reduction. An excellent example of such an application is the Hong Kong Slope Stability Warning System, wherein state-of-the-art geographic information system technology is integrated with automated data acquisition and geoengineering information of landslide triggering to issue a “landslide warning” and facilitate emergency response (see Sidebar 2.5). Adoption of statewide landslide and liquefaction hazard maps for California and their incorporation into local building codes and the widespread use of ground-shaking maps developed under the National Earthquake Hazard Reduction Program (NEHRP), with the incorporation of its methodology for developing site-specific earthquake response spectra into the International Building Code are other examples of
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation SIDEBAR 2.5 Hong Kong Slope Stability Warning System A substantial portion of the dense urban development area of Hong Kong is built on steep hillsides. Heavy rainfall triggers, on the average, approximately 300 to 400 landslides each year in these areas. To mitigate the substantial risk to life and property these landslides create among the 7 million residents of Hong Kong, the Geotechnical Engineering Office of the Civil Engineering and Development Department of the Hong Kong Special Administrative Region government has employed state-of-the-art technology to develop a sophisticated geographic information system (GIS) database to identify, register, and collect information on the approximately 57,000 slopes in the area. The GIS integrates photographs, text, and graphical information into a Slope Information System (SIS). An important component of the SIS is a sophisticated landslide warning system. The SIS is also used to facilitate maintenance planning and to coordinate emergency response. The landslide warning system is based on studies that correlate locally heavy rainfall with the occurrence of landsliding in the region. Both observed and forecasted rainfall is employed. Initially, a Landslip Warning was issued when the 24-hour rainfall was expected to exceed 175 mm or the one-hour rainfall was expected to exceed 70 mm. In 1999, enhanced criteria that take into account the size of the area receiving heavy rainfall were implemented. A total of 110 rain gauges are automatically monitored throughout the region as part of the system. In addition to data from rain gauges, radar monitoring and high-resolution meteorological satellite images are used to provide input to the landslide warning system. Three to four Landslip Warnings are issued each year. When a Landslip Warning is issued, local radio and television stations are notified and are requested to broadcast the warning to the public at regular intervals. Information is also available to local residents online and by telephone. A Landslip Warning also triggers an emergency system in various government departments that mobilizes staff and resources to deal with landslide incidents. In an emergency, the SIS provides real-time information to government agencies through an intranet. The system can be used to generate maps to show the location and seriousness of the landslides and assist an emergency controller in monitoring the situation and allocating emergency resources. The SIS also allows users to run spatial query functions and to extract slope-relevant information for planning and maintenance activities. Information in the SIS is also available to owners. The Geotechnical Engineering Office has recently implemented a mobile mapping application system (MMAS) in conjunction with the SIS. The MMAS integrates state-of-the-art mobile computing, wireless telecommunication, a global positioning system, and mobile GIS technologies into a handheld package to improve the efficiency and cost-effectiveness of geotechnical fieldwork by integrating positioning, surveying, geotechnical mapping, and data processing capabilities and to facilitate decision making under emergency situations (e.g., a serious landslide).
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation advanced geotechnology applied to hazard mitigation. While regional hazard maps have been incorporated into codes, zoning laws, and land use planning in some areas, many communities are still at risk and continued research and development is needed. Furthermore, there is an increasing susceptibility to natural hazards owing to increased urban growth. There is also a need for development of hazard assessments and mitigation measures for developing countries that are less complicated and more easily understood and applied than those used in the United States (e.g., the NEHRP methodology). There has also been increasing interest in applying formal risk assessment (see Sidebar 2.2) to geohazard mitigation, though it is not yet general practice. The adoption of reliability-based load and resistance factor design by the American Association of State Highway and Transportation Officials for its standard specifications for highway bridge construction (AASHTO, 2003) represents an attempt to move in this direction. However, most of these codes, standards and land use measures address new construction. Application of these hazard mitigation technologies to existing facilities remains a major issue that involves public policy as much as geoengineering. There have been several important initiatives for major field and laboratory experimentation relevant to geohazard assessment and mitigation since 1989, as called for in the 1989 report. These initiatives have included the establishment of seven National Geotechnical Experimentation Sites (http://www.unh.edu/nges/desc.html), the $88 million National Science Foundation-funded Network for Earthquake Engineering Simulation (http://www.nees.org), and the Federal Highway Administration-funded Interstate 15 test bed for highway research projects in Utah (Utah Department of Transportation, 2003). Geoengineers have continued to develop new technologies and enhance existing technologies for hazard mitigation. GIS are being used with increasing frequency for regional hazard assessments (Rosinski et al., 2004; Hilton and Elioff, 2004). Sophisticated numerical analyses for hazard evaluation (e.g., nonlinear earthquake site response analyses and stress deformation stability assessments) are being applied with increasing
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation frequency. Among more recent developments, automated landslide warning systems that employ time domain reflectometry and in-place inclinometers combined with automated data acquisition and interpretation and cellular or satellite communications systems are now being deployed to protect lives and property (http://www.iti.northwestern.edu/publications/tdr/1994_papers.html; Serafini and Fiegel, 2004; Kane et al., 2004). In addition to ground-based systems, airborne and satellite remote sensing systems are starting to be developed for both hazard identification and postdisaster response and recovery, though much work remains to be done in this area (Anderson et al., 2004). While there have been significant advances in geohazard assessment and mitigation technologies, global climate change threatens to dramatically increase the severity of storms and extremes of hydrologic processes (NRC, 2002a). These extremes will have larger and more serious consequences, which in some cases may lie outside of previous experience. The potential consequences of these climate extremes, including landslides, floods, and erosion, is exacerbated by growing concentrations of population in cities that are home to more than 50 percent of the world’s population (Cohen, 2003). Geoengineers will be involved in predicting these hazards and in developing mitigation plans through appropriate engineering and land use planning. However, mitigation is often linked to issues of sustainability, political and social policy, and economics. Even when the existence of a natural hazard and appropriate mitigation measures are known, political, social, and economic considerations may prevent appropriate mitigation measures from being applied. Witness over 30,000 dead in the Bam, Iran, earthquake of December 2003 with a 6.6 magnitude earthquake (USGS, 2003). Similar-size earthquakes in the United States have resulted in much less damage and loss of life (e.g., the Nisqually, Washington earthquake in February 2001, which resulted in only one death, a heart attack victim who was reported in the Seattle area [SCEC, 2001]). As with environmental protection and waste management, a major challenge for geoengineering is to develop appropriate methods for geohazard mitigation in the developing world.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation As in other geoengineering endeavors, new and improved characterization tools are perhaps the most important need in improving our ability to identify and manage geohazards. Sensing, imaging, and geophysical techniques should ultimately enable reliable monitoring of ground movements; Identification of both old landslides and new landslides that are poised to occur; Identification of expansive and collapsing soils; Location of wet, weak, potentially unstable zones in embankment dams and other critical earth structures; Identification of potentially liquefiable or otherwise unstable ground during earthquakes; Rapid reconnaissance of ground failures following an earthquake; and Identification and mitigation of other conditions and situations leading to breakdown and loss of strength in earth materials that could result in loss of stability. Regional databases and data models for geoinformation will facilitate the collection, interpretation, and dissemination of the information and algorithms required to accomplish these tasks. Landslides and earthquake-related hazards are perhaps the most dramatic geohazards, but other more subtle geohazards, such as expansive and collapsible soils, also exact a large toll on our society. The annual cost of damage to constructed facilities in the United States attributed to expansive soils was estimated to be $9 billion in 1987 (Jones and Jones, 1987), more than the annualized cost of any other geohazard in that year. Furthermore, population growth and urban growth exacerbate the impact of these natural hazards. In summary, critical issues in geoengineering for natural hazard mitigation include improved hazard monitoring and forecasting, implementation of land use planning, and development of appropriate hazard mitigation technology for developing countries. While geoengineers have
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation become fairly adept at identifying geohazards, other societal imperatives make it unlikely that hazard avoidance is a viable strategy in many land use planning situations. Therefore, hazard mitigation, including ground improvement, hazard monitoring and warning systems, and facilitation of disaster response and recovery, will remain significant geoengineering activities. Remote sensing technologies and the development of regional databases and data models will play an increasingly important role in natural hazard mitigation in the future. 2.7 FRONTIER EXPLORATION AND DEVELOPMENT Humanity has continued to stretch its reach into the deep oceans, polar regions, and outer space. Geoengineering inputs are essential for success in these endeavors. These geoengineering inputs include sampling, testing, and interpreting the results of soil and rock tests; developing advanced technologies for subsurface drilling; helping to solve trafficability and mobility problems in extreme environments; providing foundation support and developing below-surface storage; and the use of in situ materials in construction. The Apollo lunar landings from 1969 to 1972 provide a good example of how geotechnical inputs contribute significantly to the success of scientific investigations conducted in extreme environments. These lunar landings three decades ago, as well as the recent NASA landings on Mars, required consideration of vehicle mobility issues (see Figure 2.5). Any attempt to build permanent bases on the Moon or Mars, or on the seafloor, will have to address geotechnical issues as seemingly mundane as foundation-bearing capacity. Remote sensing technologies developed for interplanetary exploration may have invaluable terrestrial applications for natural hazard mitigation and subsurface exploration. The need for basic research on seafloor sediments and extraterrestrial materials identified in the 1989 report continues unabated. Exploration at the frontiers of the natural universe is considered by many a fundamental drive in human society. Frontier exploration is also often accompanied by the hope that it will lead to new frontiers for
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation FIGURE 2.5 The Lunar Rover (NASA). natural resource recovery and human habitation. Depletion of readily accessible natural resources has pushed us further and further into the frontiers of development in search of these resources (e.g., into the subarctic areas and deeper waters for mineral and hydrocarbon recovery). Inevitably, certain essential natural resources will become scarce on Earth (e.g., precious metals). Geoengineering issues are involved in both frontier exploration (e.g., vehicle mobility studies for lunar exploration and the Mars Rover) and ultimately in extraction of resources from these frontiers. Geoengineers should remain engaged in these activities as we stretch the limits of human experience and activities into these new frontiers.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation 2.8 REMAINING KNOWLEDGE GAPS Considerable progress has been made in addressing geoengineering contributions to the societal needs identified in the 1989 report in the 15 years since the report was issued. However, much remains to be done to achieve the report’s recommendations. In reviewing what needs to be accomplished, the committee identified specific geoengineering knowledge and technology gaps that must be closed. These knowledge and technology gaps include: Improved ability to “see into Earth.” Faster, more rapid, more cost-effective, more accurate, and less invasive techniques for characterizing the subsurface is perhaps the most important need in geoengineering, irrespective of the specific problem to be solved. Improved sensing and monitoring methods, including improved geophysical and remote sensing technology, more reliable and accurate instrumentation, enhanced data acquisition, processing, and storage and incorporation of the collected data into appropriate information systems. Understanding and predicting the long-term behavior of constructed facilities and earth structures, including time effects in disturbed ground. Properties and conditions change with time; our ability to predict accurately what will happen over even short time frames is limited. Improved ability to characterize both the spatial variability of soil properties and the uncertainty in soil properties and soil behavior and the associated reliability of geosystems. Characterizing and engineering with materials that are in the range between hard soils and soft rocks. Shales, mudstones, decomposed granites, and other materials are often encountered for which a determination must be made as to whether to treat them as hard rock or soil. The consequences with respect to project cost and future behavior can be large.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation Understanding biogeochemical processes in soils and rocks. Meeting this need will serve two purposes: (1) It will provide better understanding of soil and rock composition and properties and how they may change with time and (2) these phenomena and processes can open the door to both new remediation processes for environmental applications and to innovative and sustainable ground stabilization and improvement applications. Improved soil stabilization and ground improvement methods. More than ever we are forced to deal with sites and subsoil conditions that are inadequate in their present state, especially in urban areas and the megacities in both the developed and developing parts of the world. Less expensive and more effective treatment methods are needed to improve soils and rocks for use both as foundation and construction materials. Improved understanding and prediction of the behavior of geomaterials under extreme loadings and in extreme environments. Understanding and prediction of behavior under extreme loading is essential to hazard mitigation efforts. Understanding geomaterials behavior in extreme environments, including the deep ocean, polar regions, the Moon, and now Mars provide new technical and scientific opportunities and challenges. Development of subsurface databases and data models, including geological and geotechnical data, information on the built environment (e.g., subsurface utility locations), natural resource and environmental data, and monitoring data for natural hazards and environmental conditions. Applications of information-enhanced computing power, information technology, and communication systems. These applications will impact both how and what research can be done because of the opportunities for linking facilities and real-time integration of concurrent experimental, computational, and prototype analyses and observations.
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Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation 2.9 THE WAY FORWARD Beyond the context that spawned the 1989 report there are new perspectives that have introduced new needs and shifted priorities. Some of these perspectives have been discussed in this chapter and more are discussed in Chapter 4. The globalization of the economy and of our political and social environment is also a major force driving these new needs and shifting priorities. For example, rather than focusing solely on discovery and recovery of U.S. natural resources, geoengineering today must focus on global resource recovery issues and global effects of resource use. The new emphasis on sustainable development reflects the growing recognition of the forces of globalization on society and the role of the engineer. None of these issues can be considered individually because of the complex interrelationships among them. For instance, pressures from globalization impact homeland security needs, and homeland security needs impact both infrastructure development requirements and the availability of resources for infrastructure development, rehabilitation, and maintenance. There remains a host of fundamental challenges in understanding the behavior of soils and rocks and of structures composed of soil and rock that need to be addressed by geoengineers in order to more effectively deal with these issues. The United States and the world need geoengineers and need advances in their abilities to understand, manage and design in, on, and with Earth. Geoengineering is crucial to addressing essential national and global needs, including infrastructure development and sustainability, the availability and reliability of our civil structures, provision of homeland security, protection from natural hazards, and expanding our frontiers of knowledge. The following chapters will address this future. Chapter 3 examines the potential of new tools that might help to solve geoengineering problems in new and efficient ways. Chapter 4 looks at an expansion of the traditional geoengineering role into supporting the emerging fields of sustainability and Earth Systems Engineering (ESE). In Chapter 5 we examine the institutional issues at the National Science Foundation and universities that affect the attainment of the vision described in Chapters 3 and 4.
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Representative terms from entire chapter: