A Monte Carlo Investigation of a Proposed Screen for NX-Borehole Jack Data
Heuze has submitted a draft standard guide to the ASTM Subcommittee D18.12 on Rocks and Soils for using the NX-borehole (“Goodman”) jack and calculating the in-situ deformation modulus of rock masses. One aspect of the proposed standard is a “data screen” based on a full platen seating criterion. This article describes a computer simulation study that was performed to test the effect of the screen on the modulus estimate. The study demonstrates that the screen can actually degrade the quality of the estimate. It is concluded that the section of the proposed standard guide that deals with the screening of data should not be adopted.