Factors influencing correlations between CPT and DPH

Abstract

Despite the widespread availability and superior information provided by the cone penetration test (CPT), dynamic probes like the DPH (dynamic probe heavy) remain an important soil investigation method under certain circumstances. In order to make use of the results of the DPH in the context of the vast body of interpretation and design methods developed for CPT tests, the drop count N10 of the DPH is correlated to the tip resistance qc of the CPT. There are numerous correlations between both values available in the standards and in the literature. However, any soil‐related differences, limitations, and factors influencing those correlations are not necessarily obvious. The present paper presents a simple framework for the illustration of influencing factors and the interpretation of correlations between DPH and CPT. The proposed framework is based on the information provided in EN ISO 22476‐1 and published scientific literature. Linear correlation factors based on the proposed framework are derived. These factors are then compared with our own field data and information from the literature.