Testing of Drilled Shafts Socketed Into Limestone

Construction of the first phase of the South Parking Garage at the Tampa International Airport in Florida was completed in December 1991. A full-scale field load testing program was used in design of the drilled shaft foundations, with specific goals of determining the bond strength and characterizing the load-displacement behavior of the rock sockets. The displacement behavior and bond strength of the test shafts were predicted from elastic solutions and semiempirical methods. Input parameters included the rock uniaxial compressive strength and elastic modulus. The load test results are compared to the predictions herein, and the practical application of these comparisons is demonstrated by a sample evaluation of a drilled shaft supporting the South Parking Garage

Load-settlement modelling of axially loaded drilled shafts using CPT-based recurrent neural networks

The design of pile foundations requires good estimation of the pile load-carrying capacity and settlement. Design for bearing capacity and design for settlement have been traditionally carried out separately. However, soil resistance and settlement are influenced by each other, and the design of pile foundations should thus consider the bearing capacity and settlement inseparably. This requires the full load–settlement response of piles to be well predicted. However, it is well known that the actual load–settlement response of pile foundations can be obtained only by load tests carried out in situ, which are expensive and time-consuming. In this paper, recurrent neural networks (RNNs) were used to develop a prediction model that can resemble the full load–settlement response of drilled shafts (bored piles) subjected to axial loading. The developed RNN model was calibrated and validated using several in situ full-scale pile load tests, as well as cone penetration test (CPT) data. The results indicate that the developed RNN model has the ability to reliably predict the load–settlement response of axially loaded drilled shafts and can thus be used by geotechnical engineers for routine design practice