Cone Penetration Test (CPT) Based Pile Design

The CPT (Cone Penetration Test) is a miniature pile shaped device that is pushed into the ground to measure the properties of soils. Among the vast features of CPT, quantification of the bearing capacity of piles is one of the more capable features of the device due to the CPT’s similar shape to piles. Additionally, the CPT provides a continuous profile of soil response so that detailed layer information is incorporated in evaluating bearing capacity of soils, which is not possible by other techniques. A thoughtful consideration of scale factor and rate effect on the CPT result would directly provide the reliable bearing capacity of a pile foundation. This research will compare Nebraska Department's of Roads (NDOR’s) CPT data and pile loading test data, and provide a manual and spreadsheet tool to design pile foundations. The spreadsheet will provide a continuous profile of end bearing, skin friction and total bearing capacity from the tip resistance and frictional resistance information typically presented in CPT results. In addition, this proposal will compare the results of this technique with five pile loading test results from NDOR. Along with the on-going research for Piezocone, the findings of this research will be specifically tuned for Nebraska’s geotechnical conditions.