Evaluation of Design Methods for Drilled Shafts (in Florida Limestone). Volume 2 of 2

摘要

The objectives of this research were to improve understanding and design procedures of drilled shafts socketed in weathered Floridian limestones. A database of 24 instrumented drilled shaft load tests was collected, and various correlations between rock properties and engineering parameters were evaluated. Data reduction of instrumentation (sister bars and telltales) was evaluated and a computer program was prepared. Six design methodologies for rock socketed shafts were examined for capabilities in predicting capacity and settlement, as well as their required input parameters. The geological aspects of Floridian limestones were summarized. The results of the investigation showed that Florida limestones are quite varied and their properties are usually assessed by RQD, unconfined compression, and SPT N values, with the latter two being used for design. A correlation between unconfined compression and side friction shows some promise. Both telltales and sister bars perform satisfactorily; however, the former requires greater attention to detail and is more affected by temperature than the latter.