Submission of proposals
U.S. Army Waterways Experiment Station (WES)
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A00-088 TITLE: An Ultrasonic Tomography System for Imaging Reinforcement Steel in Concrete Bridge Girders TECHNOLOGY AREAS: Materials/Processes, Sensors OBJECTIVE: To design, develop, test, and demonstrate an ultrasonic tomography system for imaging the cross-sectional area of bridge girders. DESCRIPTION: From this image the user can determine the number of layers, number of bars, size, and position of reinforcing steel. Rapid movement and sustainment of troops depend upon the safe use of existing bridges to maximum capacity. To that end the bridge's Military Load Capacity (MLC) must be rapidly and accurately obtainable. A research program is currently underway at the U.S. Army Engineer, Engineering Research and Development Center (ERDC) to develop a computer-automated analytical methodology for this purpose, based upon the analytical procedures from FM5-446. These analytical methods are highly effective for most bridge types. However, in the case of reinforced or pre-stressed concrete bridges for which the internal steel reinforcement is unknown, they can only provide overly conservative, low accuracy MLC ratings. This problem became readily apparent during recent operations in the Balkans, where most of the bridges were of reinforced concrete and no steel reinforcing details were available. Conservative estimates of the internal reinforcement were necessary, resulting in possibly overly conservative MLC ratings that needlessly limited troop mobility. For this problem, a nondestructive technology is required to "look inside" the concrete and map the internal steel reinforcement. Some technologies, such as magnetic-based pachometers are currently available for this purpose. However, they are very limited in capability, especially for the typical example of multiple, deeply buried reinforcing. An ultrasonic technique known as computed tomography (CT) appears to offer a better solution to this problem. Tomography is currently being used for such purposes as imaging body parts in the medical field using both CT from X-rays and ultrasonics and from magnetic resonance imaging (MRI) and for seismic imaging of the earth. In the case of bridge girders, ultrasonic shots will be made in a wide variety of angles around the base and both sides of the girder and an overdetermined system of linear equations will be solved in real time to resolve the properties of the cross-sectional area of the girder plotted in the form of pixels. With some work, it is believed that ultrasonic tomography can be adapted for use in a military field environment for the location and definition of internal steel reinforcement. The system will be portable and user-friendly for battlefield diagnostics. The system will provide a tomogram of the cross-sectional profile of the girder. From that tomogram the number of steel bars, the size of the steel bars, and their position can be accurately determined and fed as input data into the computer-automated methodology mentioned above to aid in the determination of the MLC. Tomographic measurements require thousands of readings. In general, the final image resolution is related to the number of measurements and the coverage of those measurements. Because it is impractical to manually position the transducers for these thousands of readings, a scanning system is needed. Examples of potential technologies that might allow for practical data collection include wheel transducers, fixed arrays, and electromechanical drives. PHASE I: Determine feasibility of system and document plans for further development of hardware and software. The major tasks are to screen a few of the many seismic inversion algorithms that exist and that potentially can be applied to this problem, to image data obtained from existing ultrasonic transducers on concrete models containing reinforcing steel, and to study the potential to package a portable and user-friendly system for the field that can be easily and efficiently used by the soldier. ERDC can assist the proposer in the aspects of the ultrasonic measurements in concrete and with the field system but would expect the proposer to have significant expertise on their knowledge of inversion algorithms and their modification. PHASE II: Further screen existing inversion algorithms and refine the final inversion software to optimize the image. Provide to the computer code any a priori information about the bridge girder. For example, the concrete properties will normally be uniform and the ultrasonic velocity will lie in a narrow range. The shape of the steel is roughly circular and its velocity also lies in a narrow range. Other a priori information may be possible. Incorporate modifications to transducers such as frequency, damping, focussing, etc. that will improve the data that can be obtained with the transducers. Package scanning system, position encoders, transducers, software, computer, etc. into a field-worthy, portable, and user-friendly device. PHASE III, DUAL-USE COMMERCIALIZATION: The results of this research will have broad-based commercial potential in the development of sensor and image interpretation algorithms. Additionally, results will benefit both the civilian and military communities through the nondestructive diagnosis of concrete bridges and other reinforced concrete elements. REFERENCES: Army Field Manual, FM5-446 "Military Nonstandard Fixed Bridges". Atkinson, R.H. and Schuller, M. P. "Characterization of Concrete Condition Using Acoustic Tomographic Imaging", Phase I SBIR Technical Report, 1994. Contract Number Nuclear Regulatory Commission-04-93-094. ASTM Designation E 1441 - 97. "Standard Guide for Computed Tomography (CT) Imaging." Jackson, Michael J. and Tweeton, Daryl R. "3DTOM: Three-Dimensional Geophysical Tomography", United States Department of the Interior, Bureau of Mines, Report of Investigations No. 9617, 1996. Olson, Larry D. "Ultrasonic Tomography for Imaging of Consolidation and Other Defects in Structural Concrete", ACI Session, Oct. 1998. Stewart, Robert R. "Exploration Seismic Tomography: Fundamentals," Society of Exploration Geophysicists, Course Notes Series, Volume 3, S. N. Domenico, Editor, 1992, ISBN 0-931830-48-6 (Series), ISBN 1-56080-052-6. KEYWORDS: Ultrasonics, Ultrasonic Computed Tomography, Nondestructive testing, Imagery, Inversion A00-089 TITLE: Rapid Prediction of Pavement Performance Using Time Dependent Surface Deflection Profiles, Obtained Under Rolling Wheel Loads TECHNOLOGY AREAS: Materials/Processes OBJECTIVE: Design and build both the hardware and software components of a system for measuring pavement surface deflections that are induced by rolling military vehicles. These measurements would then be used for either: (1) predicting pavement performance under known sustained traffic or (2) classifying the pavement's structural capacity in terms of a numeric parameter, such as a military load classification (MLC) number. DESCRIPTION: Predicting the performance of a roadway over time, given traffic and environmental conditions, is an extremely complex problem. Military personnel confront this problem on a regular basis, whenever vehicles are used to move personnel or equipment. If military operations are on foreign soil, the complexity of the problem is increased by lack of knowledge concerning foundation soil, pavement material characteristics, and pavement structural thicknesses. When operating near unfriendly territory, the problem can be further complicated by lack of time and the need to keep equipment light and portable. Surface deflections can provide important information concerning the structural capacity of a roadway, and thus improve the accuracy of performance predictions (1-3). Pavement engineers commonly use nondestructive testing (NDT) equipment, such as the falling-weight deflectometer, to measure these surface deflections. These data enable engineers to predict pavement structural characteristics, such as pavement layer stiffnesses (4). These current systems, however, are not easily transported to remote locations and their usefulness is limited by the fact that the loads are imposed by the impact of a falling mass, rather than by rolling vehicle wheels. Advanced NDT equipment, such as the rolling wheel deflectometer, are under development, but these devices have shown limited success and they may never offer the portability needed for military operations. To characterize the structural capacity of a pavement section within a transportation route, surface deflections would only have to be measured under one or two critical vehicles among all the vehicles in transport. The critical vehicles would be those which impose relatively high axle loads. The two critical vehicles may differ in terms of axle configurations and/or tire pressures. Once deflections are measured under these critical vehicles, structural pavement models can predict deflections under other vehicles and thus, predict the cumulative damage imposed on a pavement by a suite of vehicle types. To ensure that the deflection measurements provide sufficient information for accurate predictions of pavement performance, the following requirements must be met. The equipment must enable the user to evaluate deflections in a single wheelpath over a roadway length of at least 4m, with individual deflection measurements spaced no more than 200 mm in the direction of travel. Measured deflections will be accurate to within 20 microns. The equipment will be able to track the position of the vehicle wheel during deflection testing. The software to be developed must provide the ability for the user to control the rate of data sampling. Data will be stored in a format that is both easy to interpret and transportable. The user will be able to view any individual deflection basin (captured at an instant in time) on a portable computer screen, along with the original pavement surface and the position of the loading wheel. The user will also be able to view deflection basins in sequence, at a user-defined rate of change. This capability will facilitate interpretation of the dynamic aspects of the problem. To ensure that the deflection measurement system is practical, it must be portable (without a trailer) and it must require no more than two hours for each test, including set-up time and execution. This time requirement is necessary because the military must be able to perform several tests in a single day. A single transportation route can require many tests because roadways are inherently variable along their lengths in terms of both internal structure and surrounding terrain. PHASE I: Conduct feasibility investigation, select the most appropriate technology, and prepare a preliminary hardware design. The feasibility investigation must describe at least three alternative technologies and it must explain the advantages of the selected technology, relative to those that were considered and were then dismissed. Preliminary hardware design must include an approximate cost of production, a description of any safety hazards, and an explanation of any availability issues related to equipment components. PHASE II: Prepare final design and construct working model. Demonstrate the model system and compare selected deflection measurements to a more traditional single-point method of measuring deflection, such as a linear variable differential transformer embedded in a test pavement. Refine the hardware and software components as deemed necessary from the demonstration. PHASE III DUAL USE APPLICATIONS: This system would be useful for pavement management applications by both military installation personnel and civilian agencies such as state departments of transportation. REFERENCES: 1. Boyer, R.E., "Predicting Pavement Performance Using Time-Dependent Transfer Functions," Joint Highway Research Project No. 32, Purdue University, West Lafayette, IN, 1972. 2. Highter, W.H., "The Application of Energy Concepts to Pavements," Joint Highway Research Project No. 38, Purdue University, West Lafayette, IN, 1972. 3. Grogan, W.P., "Nondestructive Pavement Testing and Evaluation: Facilities Engineering Applications Program (FEAP) Demonstration," Miscellaneous Paper GL-90-15, U.S. Army Waterways Experiment Station, Vicksburg, MS, 1990. 4. Bush, A.J. and Baladi, G.Y., ed., Nondestructive Testing of Pavements and Backcalculation of Moduli, ASTM STP 1026, American Society for Testing and Materials, Philadelphia, PA, 1989.
A00-90 TITLE: Advanced Multispectral Decoy Technologies TECHNOLOGY AREAS: Materials/Processes, Sensors OBJECTIVE: To design, develop, and test innovative ideas that advance the abilities of U.S. Forces and Allies to rapidly and accurately simulate an array of military targets (fixed or relocatable, stationary or mobile) by mimicking their seismic, acoustic, spatial, and spectral signatures. Techniques and concepts that reduce logistical requirements, address spatial and temporal requirements of effective deception, and can be remotely deployed, will be considered. The goal is to create in the enemy's mind a false or misleading view of the overall battlefield or specific targets within the battlefield that causes him to take actions counter to his best interests. DESCRIPTION: Newly developed lightweight materials, miniaturized electronics, and highly expansive foams are emerging technologies that can be applied to the development of advanced multispectral decoys. With the increasing dependence on remote sensing systems to provide battlespace information, new methods must be developed to rapidly and effectively counter or skew information derived from these sensors. Military decisions are based on the perceived knowledge of the opposing force's abilities, tactics, doctrine and disposition based on both human observation and electronic imagery produced by remote sensor systems. As these sensor systems proliferate, avoiding detection and concealing battlespace intentions become more difficult. This proposed effort will equally emphasize prototype development, theoretical applications, and experimental validation. PHASE I: Develop and refine decoy concepts and develop projected applications. Assess spatial and fidelity requirements. Identify potential of remotely-controlled seismic and acoustic signature generators as well as the feasibility of remotely-controlled, movable, three-dimensional decoys. Derive validation techniques to support the decoy development process. PHASE II: Develop a prototype decoy system comprised of a component sub-system allowing for the representation of multiple assets, both mobile and semi-mobile, found in a typical battlespace (i.e., tracked vehicles, fuel bladders, C3I facilities, aircraft, etc.). Develop an experimental design to validate the decoy system's effectiveness against tactical remote sensor systems. PHASE III, DUAL-USE COMMERCIALIZATION: The results of this research will have broad-based commercial potential in sensor and imagery interpretation algorithms development. Additionally, results will benefit both the civilian and military communities through an improved understanding of the requirements of human perceptions. REFERENCES: Army Field Manual, FM-20-3, Camouflage, Concealment, and Decoy Army Field Manual, FM-90-2, Battlefield Deception Joint Camouflage, Concealment, and Deception Center, JCCD Test Report Joint Camouflage, Concealment, and Deception Center, Airbase Camouflage, Concealment and Deception Guide Air Land Sea Application Center, FM 90-19, Multiservice Tactics, Techniques, and Procedures for CCD Employment in Command and Control Warfare KEYWORDS: Decoy, Multispectral, Deception, Remote Sensors, CCD A00-091 TITLE: In situ Biological Treatment for Explosives in Ground Water TECHNOLOGY AREAS: Materials/Processes OBJECTIVE: Develop and test an approach to stimulate the in situ biological degradation of explosives in groundwater. These compounds include trinitrotoluene (TNT), trinitrobenzene (TNB), and hexahydro-1,3,5-triazine (RDX). DESCRIPTION: Biodegradation of munitions contamination. The currently established method for cleaning up munitions-contaminated soils is incineration, which is both costly and environmentally disfavored. Incineration is also impractical for removing low levels of compounds from groundwater. Munitions contaminated groundwater and sediments have received substantially less attention than contaminated soils. However, as discussed above, even the relatively low munitions concentrations in groundwater may pose a threat to human health. Some studies have indicated that munitions in groundwater do dissipate over time through natural attenuation, albeit at very slow rates. The established technologies to remediate munitions contaminated groundwater include granulated activated carbon filtration (GAC) and UV-oxidation, both of which can be very costly. Phytoremediation employing constructed wetlands has been demonstrated to be effective under some configurations. Both the established and innovative methods, however, are ex situ in nature, providing treated water as an end product, but do little to actually restore the aquifer by degrading the contaminants sorbed to aquifer sediments. The proposed research will prepare protocols and examine the feasibility of in situ biostimulation and bioaugmentation to treat munitions contaminated groundwater; results will also likely lead to improvements in the ex situ bioremediation technologies as well. PHASE I: The goal of this phase of work is to develop and demonstrate, at bench-scale, a biological treatment approach using soil and ground water microcosms collected from a contaminated site or prepared with dosed soil. This work would include the comparison of different organic substrates and nutrients to optimize biological degradation. The major objective of this phase will be to identify the bacteria and determine the concentration of the organic substrates and nutrients that will lead to the most efficient and complete transformation of the munitions compounds. This must be achieved without resulting in undesirable changes in groundwater parameters (nitrate, TOC, etc.) or clogging of the sediment due to biomass growth. PHASE II: In this phase, the goal will be to demonstrate the scale-up and efficacy of the technology at pilot scale at a DoD site with the goal of developing operational data, treatment efficiency, optimization information, and a preliminary cost analysis for full-scale applications. Based on positive results obtained during the proposed research, field demonstrations and evaluation of in situ bioaugmentation, and in situ biostimulation technology may be pursued. Special emphasis will be given to determining to what extent bioaugmentation reduces start-up time, increases contaminant removal efficiencies, and ultimately reduces the overall clean-up costs. PHASE III: A full-scale site would be selected for demonstration and commercial use of the technology. Such a site could be a DoD site or a privately owned facility, and could include treatment of ground water where no previous remediation had been implemented or used to accelerate the closure of an existing pump & treat system. REFERENCES: 1. Best, E., J. Miller, M. Zappi, H. Fredrickson, S. Larson, and T. Streckfuss. 1998. Explosives removal from groundwater of the Iowa Army Ammunition Plant in continous-flow laboratory systems planted with aquatic and wetland plants. U.S. Army Corps of Engineers/Waterways Experiment Station. Report# EL-98-13. 2. Bricka, R., and W. Sharp. 1993. Treatment of groundwater contaminated with low levels of military munitions. p. 199-204. In W. E. Station (ed.), Proceedings of the 47th Industrial Waste Conference, Lewis Publishers, Boca Raton, FL, USA. KEYWORDS: Explosives, TNT, RDX, Bioremediation, Ground water contamination Topics Addressing U.S. Army Operating and Support Cost Reduction (OSCR) IntiativesDownload 1.22 Mb. Share with your friends:
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