Driven cast in situ piles: insights from a data-centric approach

Deep foundation design in general is not well served by soil mechanics theories, and geotechnical engineers typically resort to empirical design methods for routine design. The reliability of these design approaches, developed from databases of high-quality instrumented pile tests, has improved significantly over the past two decades. Predictions of shaft and base capacity for driven and cast-in-situ pile types draw upon continuous cone penetration test (CPT) profiles and other influencing factors deduced from research studies. The authors have continued this data-centric approach by focusing specifically on a commonly-used pile type called a driven cast-in-situ (DCIS) pile, a hybrid that shares elements of its installation/construction with both driven and cast-in-situ pile types. Informed by new instrumented pile research at sites in the United Kingdom with adjacent CPT profiles and a new DCIS pile database, original insights into the behaviour of DCIS piles are presented considering installation, curing, load testing, and CPT-based design, which should help to reduce risk in the design of this pile type.