Things Measured by Cone Penetration Tests other than Material Properties

抄録

The cone penetration test is a proven method for evaluating soil properties, yet relatively little research has been conducted to understand penetrometer readings (CPT-data) as a complicated boundary value problem. The interpretation of CPT-data tends to rely on empirical relationships, many of which have been developed over the years for soil identification and classification. Those studies tend to have an implicit expectation that the relationship between the CPT-data and a single soil parameter is independent, e.g. the friction angle can be estimated directly from CPT-data without the need to consider any boundary value problems. In this study, a series of numerical analysis by using FEM (GEOASIA) was conducted to demonstrate the complexity of the penetration mechanism. A description of the calculation procedures is first provided with some preliminary calculation results with various displacement ratios at the supposed cone apex. The results highlight the differences in the resistances at the cone tip even when the friction angle is the same and are evidence of the complexity of the penetration problem.