NTL Record

Title Clay Seam Mapping with Electromagnetic Induction
Record ID 75281
Personal Name
Creator
Hanna, Kanaan; Pfeiffer, Jim
Personal Name
Contributor
Haramy, Khamis Y.; Surdahl, R.; Snyder, Linden; Mohamed, Khalid
Corporate Creator United States. Department of Transportation. Federal Highway Administration. Central Federal Lands Highway Division
Corporate
Contributor
Blackhawk GeoServices Inc.
Publisher United States. Department of Transportation. Federal Highway Administration
Publication Date 20051101
Language English
Abstract The presence of swelling clay beneath roadway poses a significant problem to road rehabilitation design and construction. Roads constructed over areas of clay are generally subjected to potential differential settlement due to volume changes caused by swell/shrink and low shear strength of the clay resulting from high moisture content. If roadways with clay seams are not properly designed, a premature subgrade failure may occur and will also pose difficulties during construction resulting in higher construction costs. This report summarizes multi-phase geophysical demonstrations using various electromagnetic induction (EMI) methods on SR537 near Dulce, New Mexico. The road has had extensive surface rehabilitation due to the presence of swelling clay-rich zones in the road base. Using electromagnetic geophysical methods with rapid acquisition procedures provided a means of detecting the location of potential swelling clay-rich zones. This information was used to guide the soil boring program, thus greatly reducing the risk of missing a clay-rich zone during the site characterization planning stage and thus preventing or minimizing cost-overruns during the reconstruction phase. The results from the three-phase investigation prompted a production survey along Natchez Trace Parkway, Mississippi. The combined results from Dulce and Natchez have shown that the EMI method can provide qualitative correlations for evaluating the roadbase materials. A comparison between individual Atterberg Limits of soils obtained from the soil lab analysis and the EMI data suggests that no direct correlation can be established. However, the correlation between the bulk conductivity and the Casagrande Plasticity Classification may be used as a quick evaluation tool for predicting Casagrande soil type along the entire length of the roadway surveyed.
Public Note COTR: Khamis Haramy, FHWA-CFLHD. Advisory Panel Members: Roger Surdahl and Linden Snyder, FHWA-CFLHD, and Khalid Mohamed, FHWA-EFLHD. This project was funded under the FHWA Federal Lands Highway Technology Deployment Initiatives and Partnership Program (TDIPP).
Rosap ID dot:50038
Rosap URL https://rosap.ntl.bts.gov/view/dot/50038
TRT Terms Clay; Seams; Electromagnetic induction; Geophysical prospecting; Swelling soils; Ground settlement; Rehabilitation
General Subjects Clay; Clay seasm; Electromagnetic induction; EMI; Geophysical methods; Swelling clay; Settlement; Rehabilitation
Geographical
Coverage
United States
TRIS Online
Accession No
1751935
Contract Number DTFH68-03-00180
Report Number FHWA-CFL-TD-05-010
Resource type Tech Report
URL https://ntlrepository.blob.core.windows.net/lib/75000/75200/75281/FHWA-CFL-TD-05-010.pdf
Format PDF
Database NTL Digital Repository