The crumbling infrastructure of the United States represents an opportunity for new types of sensors, inspection equipment and repair materials. Public (Federal and state) expenditures on infrastructure have grown by 1.7% per year from 1956 to 2004 and in recent years, have been growing even more rapidly, rising by 2.1% per year, after adjustment for inflation. This rate of growth translates into a constant fraction of GDP, about 1% to 1.2%, being spent on infrastructure. The Congressional Budget Office reported that Federal and state governments spent $67 billion on highway infrastructure and $28 billion on drinking water and wastewater infrastructure in 2004.
The amount of infrastructure to inspect is enormous, according to a National Institute of Standards and Technology (NIST) white paper entitled “Advanced Sensing Technologies and Advanced Repair Materials For The Infrastructure: Water Systems, Dams, Levees, Bridges, Roads, And Highways.” The nation has 1,000,000 miles of water mains, 600,000 bridges, and 4,000,000 miles of public roadway. Public safety professionals and engineers responsible for this infrastructure strive to maintain these systems. They seek to prioritize repair schedules and to avoid premature replacement of infrastructure. Better technologies have the potential to provide invaluable input to these recommendations by making the monitoring of processes and conditions that affect structures more quantitative, more thorough, and more frequent. Technologies that achieve the goal of continuous monitoring of structural integrity with costs low enough to permit wide-scale, permanent deployment, require transformative research.
The societal challenges—needed improvements in cost-effective inspection and monitoring of critical infrastructure systems, and transformational improvements in materials and technologies for application of these materials, particularly those for application to water delivery systems, wastewater mains, dams, levees, bridges, and roadways—can potentially be resolved with better and more cost-effective technologies. Real-time data on the structural integrity of infrastructure components is not only useful for determination of repair and retrofit scheduling, but also for emergency notification in the event of impending catastrophic failure.
There are currently no cost-effective, field-deployable sensing systems that are capable of providing continuous data with which to prioritize repair and retrofit schedules and that provide sufficient warning of impending catastrophic failure. There has been progress in the development of embedded sensors for new construction; however, these systems are not deployable to existing components of the infrastructure. It is clear that both the EPA and the FHWA concur that current infrastructure inspection and monitoring systems are inadequate and that better infrastructure sensing systems, based on current state of the art technologies, are either not available or not economically feasible. An analysis of the gap between these societal challenges and the investment in solutions to these challenges found insufficient funding of truly transformative research, as opposed to research directed at making incremental improvements, in the areas of materials and processes for repair of infrastructure elements.
New sensing technologies that produce real-time (time-effective) monitoring data, and that can also help or aid in the interpretation of the acquired data, therefore will enhance the safety of the public by issuing timely and accurate alert data on structural integrity. New sensing technologies will also allow more informed management of infrastructural investments by avoiding premature replacement of infrastructure and identifying those structures in need of immediate action. New repair/retrofit materials and means to implement material solutions will complete the infrastructure manager's toolkit to address more effectively the challenges presented by aging infrastructure.
The NIST Technology Innovation Program has decided to invest again in "Advanced Sensing Technologies and Advanced Materials for the Infrastructure: Water Systems, Dams, Levees, Bridges, Roads and Highways." Within the Critical National Need of civil infrastructure, these new technologies will provide increased lifetimes, security and safety of elements of critical infrastructure. The vision for this funding opportunity is:
• To develop new tools and techniques that will enable infrastructure managers to monitor the structural health of critical national infrastructure elements that are essential for the health of the nation, its economy, and its citizens;
• To develop the means to sense the safety, security, and integrity of engineered structures above ground, in ground, and below water surfaces, that are within the nation’s highway, water, wastewater, and water control systems that provide that information to managers of these systems in a time-and-need effective manner; and
• To develop novel advanced materials and/or novel application technologies that will make more economical repairs or retrofits and extend the usable lifetime of existing civil infrastructure.
In general, local and state governments have significant knowledge gaps regarding quantitative assessment of infrastructure integrity, yet they do not have the funds and ability to develop more cost-effective advanced sensing tools that would eliminate the knowledge gaps or to develop advanced materials and application technologies that would provide long-lived repair of defective or deteriorating structures.
One Federal research program targets advanced sensing for infrastructure – the National Science Foundation’s “Sensor Innovation and Systems Program.” Total funding for this program is $5 million per annum and innovation in sensing is only one of several categories of research supported under this program. Other programs were identified in which new sensing technologies might be funded, but none of the programs is targeted specifically at new or early stage sensing technologies. The civil infrastructure grants that are provided by the National Science Foundation (NSF) are primarily targeted for academic fundamental research and are smaller than those of TIP.
The Exploratory Advanced Research Program of the Federal Highway Administration (FHWA/USDOT) is currently targeted at Intelligent Transportation projects. The Remote Sensing and Spatial Information Program of the Research and Innovation Technology Administration (RITA/USDOT) is a university-focused program that asks applications to use existing technologies in a transportation context. Those seeking further information should consult the Federal Funding Opportunity notice.
The National Institute of Standards and Technology (NIST) is asking for public comment on white papers that outline potential areas for research funding grants under the Institute’s Technology Innovation Program (TIP) including: Advanced Sensing Technologies and Advanced Repair Materials for Infrastructure: Water Systems, Dams, Levees, Bridges, Roads, and Highways, available at www.nist.gov/tip/wp_cmts/civil_wp_11_5_09.pdf (comments to be sent to civil.tipwp@nist.gov);