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Underground Engineering for Sustainable Urban Development (2013)

Chapter: Appendix C: Interdisciplinary Underground Engineering Practice

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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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C

Interdisciplinary Underground Engineering Practice

This appendix focuses on an integrated systems approach to the practices of urban planning, underground development, and maintenance and discusses the multidisciplinary effort required to manage underground infrastructure in an integrated way throughout infrastructure lifecycle. Contracting practices are also discussed.

THE INTERDISCIPLINARY UNDERGROUND ENGINEERING TEAM

Underground engineering is a multidisciplinary endeavor given the challenges associated with creating healthy, safe, productive, and pleasant space in complex geologic environments and in inhospitable and dangerous conditions. A range of considerations—from social, political, and economic, to physical condition of the ground, to environmental preservation, to those related to human factors—play into decisions to be made by the necessarily interdisciplinary teams that plan, construct, operate and maintain. Some specialties tapped during planning and construction are described in this appendix to demonstrate the complexity of engineering underground infrastructure with sustainable development in mind. The sections are broken into distinct phases or specialty areas, but successful project completion depends on an integrated approach and constant interaction among team members.

Early Planning for Sustainability

During early underground infrastructure planning for a representative project, urban and regional planners consider opportunities to optimize the surface

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

environment through underground use. Specialized site and facility planning specialists consider the interrelationship between the surface and underground in detail. Architects, architectural engineers, and underground civil engineering specialists develop and illustrate workable design solutions for specific underground spaces that reflect geologic and groundwater conditions and any hazards present at and near the site of the proposed facility. Geotechnical engineers provide site definition investigations and studies that establish the basis for these designs (see below). To appreciate what the finished facility may look like and how well it will serve the intended purposes, interior designers will consider how to transform the underground space by planning surfaces, lighting, colors, finishes, textures, signs, and subliminal indicators that contribute to a sense of comfort and safety in the underground and its public access points.

Cost Estimating, Schedule Management, and Interface Management

A component of project “success” is completion within cost budgets and time schedules. Cost and schedule management specialists develop workable schedules and correlated cost estimates for the underground work that reflect reported site conditions and constraints, equipment selection to perform the work, and any mitigations designated by the various government offices with jurisdiction. As the project advances to construction, the leads on the interdisciplinary team, define major discrete work elements and implement control systems that assist in the management of project scope, costs, and schedules beginning with a project work breakdown structure (WBS). They coordinate cost estimates, time schedules, and data that form baseline working budgets for each task and work package. A critical path schedule is developed to aid work management. The assembled information becomes a regularly updated project control system that reflects progress and identifies occurrences of indications of problems or delays as early as possible. Underground project cost estimating specialists conduct risk and contingency analyses, analyze processes and scheduling, and recommend the most cost effective equipment for specific jobs. They rely on the work of underground systems engineering specialists who develop a project risk register1 used in project planning, risk assessment, and risk mitigation.

Systems engineering specialists, besides developing risk registers, employ interface management techniques that integrate project management areas and technical disciplines. As a project develops, construction contract packages are defined for different parts of the project, and interfaces between the separate

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1 A risk register is a tool created shortly after a project concept is defined, and is used to manage risk in underground construction and operation throughout project development. It helps to identify risks and their impacts, from which mitigating and contingency actions can be determined. Many risks listed in the register (e.g., discipline-specific uncertainties such as the availability of specific electronic devices) are reduced as work progresses and mitigation activities are performed.

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

contracting packages coming from different contractors must be identified and actively managed. Other systems engineering assignments may include configuration management (assuring system function and performance are consistent with design) and change control management. A small, well-lead group of experienced procurement practitioners will prepare and proof contract documents and oversee procurement processes for the several underground contracts to be bid and built.

Site Characterization and Environmental Protection

Engineers with training in many disciplines are necessary to characterize the underground, re-engineer existing infrastructure, and create the environment necessary to support the proposed underground infrastructure. The expertise of civil engineers trained in the design, construction, and maintenance of public works is augmented with expertise of those with graduate training in areas such as geotechnical and geological engineering, rock and soil mechanics, and geophysics.

Geotechnical engineers classify the engineering behavior of earth materials through field and laboratory testing. Geological engineers interpret how the geology and geologic origins of an area might influence planning, mining, construction, and operation of the infrastructure. Understanding the soil and rock mechanical properties at and near a job site is necessary for smart and safe design and construction of proposed underground structures. Rock mechanics engineers describe expected in situ strengths, stresses, strains, elasticity, and other rock mass properties where work will occur. Soil mechanics engineers similarly describe the nature and behavior of the less consolidated materials—soils—in the area. In the early design and development of the project, these various specialists prepare a geotechnical baseline report (GBR),2 take part in specifying and selecting tunnel boring machines (TBMs), and, as designs develop, work with the design and specification drafting team. Geophysical engineers noninvasively measure physical properties of an area using equipment and analytical techniques to infer geology, geologic structure, groundwater conditions, to identify geologic anomalies where they exist, and the presence of manmade artifacts or potentially dangerous gases. This aids production of three-dimensional models of soil and rock characteristics. Gaseous ground mitigation specialists will design measures to mitigate and control each type of gas.

Groundwater Protection and Control

Environmental engineers and planners identify potential impacts to the environment associated with underground infrastructure construction and work with

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2 A GBR is used to define the baseline conditions on which contractors will base their bids and select their means, methods, and equipment (FHWA, 2011a).

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

design engineers to identify appropriate construction plan, operation and mitigation measures. An environmental impact report or statement is completed before the design of any project begins in earnest, and mitigation action plans—as needed—will be part of submitted planned contract bid packages. Project delivery that includes mitigation measures is a means to assure environmental protection.

Groundwater hydrology engineers address challenges associated with protecting groundwater as a resource, and with engineering in consideration of groundwater as a component of the soil and rock. The control of groundwater, commonly encountered during underground construction, is a complicated and potentially costly physical challenge. It is important that groundwater conditions at infrastructure works shafts and surface penetrations are mapped and analyzed, and that groundwater preservation and management solutions are developed and coordinated with all team members. Groundwater conditions can influence a series of fundamental decisions related to construction and operation, including choice of ground excavation methods, support systems, and of water barriers that may be required to protect groundwater resources and maintain a “dry” underground facility.

Facility Construction

Once construction begins, structural engineers lead units charged with the design of specific project sections or elements (normally what becomes a construction contract package). These engineers know how appropriate connections between the different structural components are made, and may have to incorporate seismic design and waterproofing concepts into underground structures to make structures safe for given circumstances. Seismic engineers evaluate for and prepare site-specific seismic designs criteria to assure compliance with existing codes and safety. Geotechnical engineers, TBM specialists, and mining engineers may be enlisted as part of the team to allow safe excavation of materials from within the earth.

Building underground facilities, as with many aboveground facilities, requires the expertise of underground works construction engineers who understand problems associated with crowded work sites and difficult logistical considerations. Work sequences can become disordered by small events that result in delays and added costs. A seasoned construction engineer performs full constructability reviews to anticipate such problems as the designs develop.

Mechanical, Electrical, and Communication Systems

Trained mechanical engineers design, construct, and operate, multiple mechanical systems needed in underground projects, including water management (e.g., sumps and piping, valves, pumps and motors, and controls), and heating, air conditioning, and ventilation systems. Mechanical equipment needs

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

to be selected consistent with existing codes and standards, with energy efficiency in mind, and in consideration of the underground environment and sustainable use. Underground safety is enhanced through application of computational fluid dynamics techniques to determine how fluid and gasses flow in and around underground spaces. Noise mitigation and the safety and comfort of occupants of the underground are also of concern to mechanical engineers. Electrical and communications systems engineers design power transmission, distribution and communications systems, and the surveillance and security sensors, systems, and control rooms from which these systems are operated. Electrical systems are essential to the work of many other engineers on a given project, and to safe infrastructure operation.

Fire Protection and Life Safety

Assuring the safety of people underground requires accommodating the physical needs of survival. Ventilation experts design systems to provide fresh air and remove excess carbon dioxide and other gases that build up in enclosed spaces. Fire safety specialists understand how underground fire may start, spread, be contained, and extinguished, and they understand how smoke, heat, or hazardous materials may travel through underground passageways and pose threats. They also understand how many emergency evacuation routes are needed and where they can be placed, and under what circumstances shelter-in-place facilities might be appropriate. Each underground project is under the jurisdiction of fire marshals who guide infrastructure design to satisfy fire and life safety requirements, however safety and sustainability are often dependent, especially in the underground, on moving beyond regulatory compliance.

Although not generally considered a primary purpose in the United States, underground infrastructure may be called upon to shelter people against natural or manmade hazards. Shelter design engineers or weapons effects experts may be asked to integrate the requirements of such use into facility design.

UNDERGROUND CONSTRUCTION CONTRACTING PRACTICES

Underground construction contracting, as with all types of construction contracting, ranges from small and simple to large and complex. Project contracting differs depending on the scope, work site location, sources of funding, if the project will be built by union employees or “open shop”, and applicable laws, ordinances, and regulations. Contract provisions unique to underground construction practices, however, have been developed according to site geology and groundwater conditions, site uncertainties and risks, special project insurance provisions, and payment terms corresponding to risks shared by the owner and contractor. Such provisions have been formalized with support of the underground construction industry and successive blue ribbon committees comprised

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

of experts from federal agencies, the engineering and construction industry, academe, and the legal services and insurance industries. The National Research Council’s U.S. National Committee on Tunneling Technology (USNCTT) produced reports from 1974 through 1995 covering contracting and technical issues intended to improve the performance of underground construction (NRC, 1974; 1977; 1978; 1984; 1989; and 1995).

Summaries of Key USNCTT Issues

The body of work from the USNCTT improved contracting and management practices for underground construction in the United States. Their reports are still important resources today, remaining relevant in the face of derivative laws of the National Environmental Policy Act of 19693 that cover water, air, noise, endangered species, remediation, as well as the introduction of much new technology. The value of the work of the USNCTT in improving contracting practices and management for underground facilities is illustrated in the following summaries of issues addressed in their reports. The American Society of Civil Engineers (ASCE 1997, 2007), the Underground Construction Association4 and the International Tunneling Association (e.g., ITA, 1988) more recently have addressed improvements to construction contracting for underground works. Below are descriptions of key reports.

Better Contracting for Underground Construction (NRC, 1974) provides recommendations pertaining to:

• Full disclosure to all bidders of all subsurface information, professional interpretations, and design considerations through a special report of geotechnical site conditions and facility designs, with careful distinction given to what was factual data and what were interpretations or opinions. The report spoke out against the use of disclaimers by owners pertaining to underground geotechnical data provided.

• Provisions for a changed-conditions clause within contracts to include differing-site-conditions thus identifying for the owner where it might assume the risk concerning unknowns in subsurface physical conditions.

• Provisions for contingencies for special groundwater problems.

• Encouragement of the use of cost-reimbursement contracts for major underground construction with particular terms and conditions.

• Provisions for bidder pre-qualifications.

• Provisions for use of value engineering.

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3 See www.epa.gov/lawsregs/laws/nepa.html.

4 See http://uca.smenet.org/.

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

• Provision for the use of bid pricing to provide for timely payment for up-front mobilization and other expenses for the contractor, and alternative bidding for private work but not for public works (contrary to then-existing public laws).

• Provisions covering cost escalations during the contract period.

• Provisions to substantially reduce the time and cost of submitting, negotiating and obtaining payment of contract price adjustments for approved changes.

• Disclosure of the engineer’s estimate for the cost of the construction as-bid with the opening of bids; and, disclosure with the invitation for bids, providing notice given a limit on the total funding available for the contract.

• Provisions for wrap-up project insurance.

• Provisions for use of the arbitration process, a process developed by the American Arbitration Association (AAA) to settle disputes under the contract, short of litigation.

These recommendations left open the use of disclaimers by an owner when providing site geotechnical data and information for prospective underground construction bidders and construction managers. This proved to be a significant opportunity for disputes and litigation centered on this issue, which the committee was soon to address.

Recommended Procedures for Settlement of Underground Construction Disputes (NRC, 1977) detailed the processes for employing the AAA procedures that included in contracts:

• Provisions to employ AAA’s underground construction disputes settlement rules to settle disputes equitably and cost effectively through the use of both mediation and arbitration.

• Provisions for either party, if in their interest, to call for the matter in dispute to go to arbitration, with the knowledge that the arbitration report would be entered into evidence should the matter ultimately go to litigation.

The use of the mitigation or arbitration process brought into focus the need for experienced underground construction experts who could objectively hear the arguments for and against a disputed issue and find a suitable resolution based on the contract, technical considerations, the law and precedence and also be versed in the process. If mitigation was employed, a single party acceptable to both could handle the process and matter. However if the matter was taken to arbitration, the process typically would entail a panel of three persons. This process initially worked, but was costly, time consuming, and the number of people qualified for the processes was limited.

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

This led to the advent and use of construction-industry organized and populated, Dispute Review Boards (DRB), (called Disputes Resolution Boards in some states) based on the form of the arbitration process, but entirely staffed with senior and semi-retired experienced underground construction personnel, first used in 1975. Their proceedings were found to take less time, cost less, to be more amicable, and more equitable in their outcome. Thereafter the Disputes Resolution Board Foundation was formed to provide a central source of information and optional form-contract terms for use across the United States and throughout the world.

Better Management of Major Underground Construction Projects (NRC, 1978) observed that underground projects are among the most complicated because they typically take place in urban areas, geotechnical considerations assume greater importance than in other types of construction, and underground work requires special equipment, techniques and skills to perform. The success of underground projects is therefore particularly sensitive to the management practice employed. The report provides recommendations to address and avoid management problems of projects through the use of examples. The report identifies that the most important cause of management problems is delay in taking decisive action. A list of goals and objectives to improve the management of underground projects is provided and detailed.

Geotechnical Site Investigations for Underground Projects (NRC, 1984) which provided an entirely new strategy for improving contractor/owner relationships and outcomes related to underground projects. This was a strategy for fair risk sharing, particularly of those associated with unknown ground conditions. Complete disclosure of all factual geotechnical information to all bidders, and the preparation of a special report that documents the designer’s reasoning and interpretations that resulted in the selection of construction methods, lining types, anticipated ground behavior and other information was recommended.

Central to this new contracting strategy was an appendix to the report entitled Geotechnical Design Report (NRC, 1984). With the use and purpose remaining the same, practitioners in the industry found it more convenient to rename it “Geotechnical Design Summary Report” (GDSR). In 1997, the ASCE through its Underground Technology Research Council, Technical Committee of Contracting Practices expanded and added clarity and form of the GDSR document, revising the title to Geotechnical Baseline Report (GBR) (ASCE, 1997). ASCE and others have continued to improve the GBR in application (e.g., Smith, R.E., 2001; van Staveren and Knoeff, 2004; ASCE, 2007; and Rozek and Loganathan, 2008). There is a continuing need to update the content of the GBR and to anticipate the geotechnical and design requirements for use of new technology in ground improvement tools and materials, new mining tools and capabilities, etc. coming into the construction processes. Ongoing research is indicated.

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

In 1989 the USNCTT addressed the anticipated construction of the Superconducting Super Collider (SCC; 72 miles of tunnels, 42 shafts, 4 large underground rooms, etc.). Recommended contracting practices for this project, addressed effective use of rigorous risk recognition, risk assessments and minimizing, and allocation of risks on the basis of what party can best manage the risk or consequences.

The SSC project team was to identify then mitigate, minimize, control, or eliminate project risks to the performance of the underground work. These recommendations were applied by the project team at every step with the outcome that with over $400 million in construction completed or in work under firm fixed price construction contracts, the project was $100 million under the project’s target cost for that scope when the government terminated the project in 1993 (P. Gilbert, personal communication).

Safety in the Underground Construction and Operation of the Exploratory Studies Facility at Yucca Mountain (NRC, 1995) issued its last report on the topic of safety. It is interesting that the always significant issue of underground work safety was addressed in this last USNCTT publication.

The beneficial contributions made to U.S. underground construction practices cannot be overstated. Revisiting the need for a body that could provide unifying guidance related to the full array of underground infrastructure issues for the lifecycle of said infrastructure may be appropriate, especially with respect to how underground engineering practice may ultimately contribute to urban sustainability.

REFERENCES

ASCE (American Society of Civil Engineers). 1997. Geotechnical Baseline Reports for Underground Construction: Guidelines and Practices. Reston, VA: American Society of Civil Engineers.

ASCE. 2007. Geotechnical Baseline Reports for Construction – Suggested Guidelines, R.J. Essex, ed. Reston, VA: American Society of Civil Engineers.

FHWA (U.S. Federal Highway Administration). 2011. Chapter 4 – Geotechnical Reports. In Technical Manual for Design and Construction of Road Tunnels – Civil Elements. U.S. Department of Transportation. Available at http://www.fhwa.dot.gov/bridge/tunnel/pubs/nhi09010/04.cfm.

ITA (International Tunnelling Association).1988. ITA ecommendations on contractual sharing of risks. Tunn. Undergr. Sp. Technol. 3(2):103-140.

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×

NRC (National Research Council). 1974. Better Contracting for Underground Construction. Washington, DC: National Academy of Sciences.

NRC. 1977. Recommended Procedures for Settlement of Underground Construction Disputes. Washington, DC: National Academy of Sciences.

NRC. 1978. Better Management of Major Underground Construction Projects. Washington, DC: National Academy of Sciences.

NRC. 1984. Geotechnical Site Investigations for Underground Projects, Volume 1 and 2. Washington, DC: National Academy Press.

NRC. 1989. Micro and Small Diameter Tunneling. Washington, DC: National Academy Press.

NRC. 1995. Safety in the Underground Construction and Operation of the Exploratory Studies Facility at Yucca Mountain. Washington, DC: National Academy Press.

Rozek, J., and N. Loganathan. Geotechnical Baseline Report as an Underground Risk Management Tool. Parsons Brinkerhoff, Sydney Australia [online]. Available: http://www.ctta.org/FileUpload/ita/2009/papers/O-01/O-01-05.pdf (accessed October 2, 2012).

Smith, E.R. 2001. Geotechnical Baseline Reports: State of the Practice. Proceedings 36 Annual Symposium on Engineering Geology and Geotechnical Engineering, Luke, Jacobson & Werle (ads) Univerity of Nevada, Las Vegas, March 28-30.

van Staveren M.T. and J. G. Knoeff. 2004. The Geotechnical Baseline Report as Risk Allocation Tool. In Engineering Geology for Infrastructure Planning in Europe. R. Hack, R. Azzam, R. Charlier (Eds.). pp. 777–785. New York: Springer.

Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
×
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Suggested Citation:"Appendix C: Interdisciplinary Underground Engineering Practice." National Research Council. 2013. Underground Engineering for Sustainable Urban Development. Washington, DC: The National Academies Press. doi: 10.17226/14670.
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Underground Engineering for Sustainable Urban Development Get This Book
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For thousands of years, the underground has provided humans refuge, useful resources, physical support for surface structures, and a place for spiritual or artistic expression. More recently, many urban services have been placed underground. Over this time, humans have rarely considered how underground space can contribute to or be engineered to maximize its contribution to the sustainability of society. As human activities begin to change the planet and population struggle to maintain satisfactory standards of living, placing new infrastructure and related facilities underground may be the most successful way to encourage or support the redirection of urban development into sustainable patterns. Well maintained, resilient, and adequately performing underground infrastructure, therefore, becomes an essential part of sustainability, but much remains to be learned about improving the sustainability of underground infrastructure itself.

At the request of the National Science Foundation (NSF), the National Research Council (NRC) conducted a study to consider sustainable underground development in the urban environment, to identify research needed to maximize opportunities for using underground space, and to enhance understanding among the public and technical communities of the role of underground engineering in urban sustainability.

Underground Engineering for Sustainable Urban Development explains the findings of researchers and practitioners with expertise in geotechnical engineering, underground design and construction, trenchless technologies, risk assessment, visualization techniques for geotechnical applications, sustainable infrastructure development, life cycle assessment, infrastructure policy and planning, and fire prevention, safety and ventilation in the underground. This report is intended to inform a future research track and will be of interest to a broad audience including those in the private and public sectors engaged in urban and facility planning and design, underground construction, and safety and security.

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