Force Projection Site Evaluation Using the Electric Cone Penetrometer (ECP) and the Dynamic Cone Penetrometer (DCP).

World political and economic changes over the last decade have dictated the United States Air Force (USAF) to alter its concept of operations from prepositioning forces to projecting forces into the needed area. This force projection concept generates a requirement for rapid, accurate assessment of an unfamiliar airfield's load-carrying capability with minimum logistical support. USAF development of dynamic cone penetrometer (DCP) and electric cone penetrometer (ECP) capabilities have aided in meeting this requirement. This study is to develop better correlations between ECP results and California Bearing Ratio (CBR) and DCP results and CBR. These correlations are essential since current evaluation charts relate allowable aircraft loads and passes to CBR. Field tests were conducted on existing airfield pavements at Maxwell AFB, AL. In addition, 28 test items reflecting a broad spectrum of materials, densities, and water contents were constructed and tested at the U.S. Army Engineer Waterways Experiment Station. This report presents the correlations developed between ECP results and CBR and between DCP results and CBR. Other significant findings of the study were (a) the ECP is an effective tool for classifying soils, (b) both the ECP and DCP can produce strength versus depth profiles, and (c) both the ECP and DCP are capable of identifying layer interfaces.