Closure to 'Predicting End Bearing Capacity of Post-Grouted Drilled Shaft in Cohesionless Soils' by Gray Mullins, Danny Winters, and Steven Dapp

摘要

The authors appreciate the discussers' interest in this topic and the time taken to submit a discussion. Therein, the use of rapid load testing and the various analysis methods were of interest to the discussers, along with the pressure state of grout while it cured. Although some of these points can be gleaned from the paper, procedures and "how-to" knowledge could not be adequately addressed without detracting from the intended design emphasis.rnRapid load tests were used on all shafts in the original studies whereby both inertia and damping corrections were applied, which became standard ca. 1995 (Middendorp 1995). This included both the grouted and ungrouted shafts. Methods for establishing the shear stress and displacement distribution throughout the shaft are commonly applied using the segmental unloading point method (Lewis 1999; Mullins et al. 2002). Thereby, toe displacements are computed from the measured strain distribution and the top of shaft movement for each measured time interval. In most of the test shafts used in the presented study, toe accelerom-eters were also used to corroborate the computed values.