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Opportunity at Federal Highway Administration (FHWA)

Variability of Strength-Deformation Characteristics of Open-Graded Aggregates


Federal Highway Administration

RO# Location
27.01.00.C0246 McLean, VA 221012296


name email phone
Jennifer E Nicks 202.493.3075


The Federal Highway Administration’s Turner-Fairbank Highway Research Center (TFHRC) has performed extensive testing on crushed, manufactured open-graded aggregates (OGAs) at both loose and dense states using a large-scale direct shear device (LSDS). This has led to a better understanding of the strength of AASHTO M 43 aggregates for use in design. To date, however, many of the test results have been mostly of a similar source aggregate, tested in the same laboratory. To expand the viability of these results, a study has been initiated to test aggregates from many different sources/quarries in various labs, including sieve analysis vibratory table testing, and large scale direct shear testing. This will allow an evaluation of the variability of the results and the corresponding statistics on strength, dilation angle, “cohesion,” maximum density, etc. for use in future Load and Resistance Factor Design (LRFD) calibrations.

A researcher is primarily needed to assist with: (1) coordination and communication, (2) sample collection and testing, (3) evaluation of new and existing test results from various laboratories, and (4) statistical quantification of the results. Depending on the timeline and schedule of this investigation, additional tasks may be assigned to the researcher for assistance with various other ongoing or planned research performed at the facility.

Geotechnical; Aggregates; Soils; Variability; LRFD; Direct shear; Laboratory testing


Citizenship:  Open to U.S. citizens, permanent residents and non-U.S. citizens
Level:  Open to Postdoctoral and Senior applicants


Base Stipend Travel Allotment Supplementation
$65,000.00 $4,000.00

Experience Supplement:
Postdoctoral and Senior Associates will receive an appropriately higher stipend based on the number of years of experience past their PhD.

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