Stochastic and Centrifuge Modelling of Jointed Rock. Volume 2. CentrifugeModelling of Jointed Rock

摘要

The use of the centrifuge for geotechnical research has gained widespreadacceptance in soil engineering, but to date, relatively few tests have been performed involving rock. One reason for the scarcity of rock mechanics experiments is the question as to whether a small scale model subject to an elevated gravitational acceleration level reasonably simulates the prototype condition involving discontinuities. The objective of this research was to find out if centrifuge modelling can be used for discontinua and to get further insight into arching mechanisms. To investigate this issue of scaling, a modelling-of-models approach was followed. This was done with a trapdoor model in the centrifuge. The model package was spun up gradually to a desired gravity level, at which the trapdoor was lowered and measurements of the force on the door with the corresponding displacement were taken. Different sizes of small-scale models and of trapdoors were used with various levels of acceleration. An initial series of experiments was conducted with granular materials, namely, New Jersey coarse sand and uniform sized glass beads. These experiments not only allowed us to make comparisons with preceding experiments on the arching mechanism under normal gravity; they also served as a benchmark for the experiments with jointed rock.