Tumay Rapid growth and boom in surface construction and underground infrastructure in U.S. cities and suburbs increases the demand on geotechnical engineering. Geotechnical engineers are facing increasing challenges to improve in-situ testing tools for accurate site characterization of soil properties and efficient evaluation of geomedia improvement. The piezocone penetrometer test (PCPT) is a simple, fast, and repeatable test that can provide continuous soundings of the subsurface. The PCPT test data can be effectively utilized for soil stratigraphy and identification, and the evaluation of engineering soil properties.

The use of piezocone penetrometer for site investigation is currently limited to vertical testing. The vertical intrusion of the cone penetrometer is not always possible due to existing obstructions and/or lack of access. Moreover, in many cases the soil strength parameters and/or flow characteristics are needed at an inclination plane due to the nature of soil (i.e. bedding, inclined foundation) or the alignment of reinforcing structure (i.e. soil nails, batter piles). The use of piezocone for inclined penetration has not yet been thoroughly investigated.

The main objective of this research is to extend the application of piezocone penetrometer by intrusion at different inclination angles, and to bring out the fundamental aspects (experimental and theoretical) of the inclined penetration. Many questions remain to be answered and interpretation methods need to be developed before the inclined piezocone penetration is applied to practice. The influence of the angle of inclination and soil anisotropy on the cone tip resistance, sleeve friction, generated pore pressures and their dissipation will be investigated. The inclined piezocone penetration will be analyzed using the finite element methods. The outcome of this research will set the standard towards the inclined use of the piezocone penetrometer for site investigations in locations where it is impossible to perform vertical penetrations, and whenever strength and consolidation parameters at a horizontal or inclined direction are needed, as in soft ground tunneling.

This research will have a significant impact toward improving subsurface investigation and introducing a new technique of inclined piezocone penetration testing and its interpretation to accurately evaluate soil properties for better design and analysis. It will also help in understanding the effect of the soil's inherent and induced anisotropy so that better interpretation methods can be developed. ***

Agency
National Science Foundation (NSF)
Institute
Division of Civil, Mechanical, and Manufacturing Innovation (CMMI)
Application #
9907951
Program Officer
Richard J. Fragaszy
Project Start
Project End
Budget Start
1999-10-01
Budget End
2005-05-31
Support Year
Fiscal Year
1999
Total Cost
$202,312
Indirect Cost
Name
Louisiana State University & Agricultural and Mechanical College
Department
Type
DUNS #
City
Baton Rouge
State
LA
Country
United States
Zip Code
70803