Open Competition 1 - Information Technology

Integration of 3-D Ground Imaging Technologies with Numerical Modeling for Civil Construction Design

Sponsor: NSA Geotechinical Services, Inc. (formerly NSA Engineering)

• Project Performance Period: 9/1/2001 - 8/31/2004
• Total project (est.): $2,301,979.00
• Requested ATP funds: $1,997,000.00

Design, construction, and maintenance of the nation's massive civil infrastructure, from highways to dams to sewers, must take into account the highly variable attributes of the surrounding ground. Existing site characterization and geotechnical engineering methods, such as core drilling and well monitoring, are error prone, leading to problems estimated to cost society more than $20 billion annually. To provide more comprehensive and realistic descriptions of ground attributes, NSA Engineering Inc. plans to combine seismic tomography and holography -- imaging methods equivalent to computed tomography scanning used in medicine -- to estimate locations and material property variations for use with numerical modeling techniques. Information on how waves propagate in ground materials will be used to construct acoustic data, which then will be used to calibrate numerical models, thus providing visual engineering graphics of the three-dimensional rock-soil mass. The three-year project will require a range of innovations, because existing simulations cannot accurately match model parameters with actual site conditions, and current imaging methods are too costly or otherwise inappropriate for civil infrastructure applications. Technical challenges include the development of automated signal processing methods for comparing field-acquired seismic signals to model-generated signals, integration of the various elements into a comprehensive design package, and control of uncertainty and noise in the data to provide the level of accuracy required. The ATP funding will greatly accelerate the development of this technology, enabling the U.S. construction industry to maintain an advantage over foreign competitors. Technical support will be provided by the Colorado School of Mines (Golden, Colo.) and University of Colorado (Boulder, Colo.). If successfully developed, the new technology will provide accurate knowledge of ground conditions that will reduce project risk and cost, improve construction performance and safety, and prolong structure life. The innovations also could be useful in other fields that rely on modeling of energy transmission; examples include forensic earthquake analysis and medical ultrasound.

For project information:

Matthew J. DeMarco, (303) 277-9920
demarco@nsaengineering.com

ATP Project Manager

Christopher Currens, (301) 975-8503
christopher.currens@nist.gov