Theoretical and Laboratory Study of Deep-Based Structures. Volume I. Triaxial Machine for Static and Dynamic Testing of 12-Inch Diameter Rocks.

摘要

Design and fabrication of large-scale testing machine for static and dynamic testing of rock cavity reinforcement is described. The machine is patterned after a smaller prototype developed previously for DNA. The larger-scale machine can be used to apply static and dynamic triaxial loads on specimens that are 12 inches (0.3 m) in diameter and 12 to 18 inches (0.3 to 0.45 m) high, with rock cavities 2 inches in diameter. A variety of triaxial loadings are possible which permit laboratory simulation of different loadings imposed on deep-based structures in the field. The machine can apply vertical pressures up to 2 kbar (0.2 GPa) statically and to 1 kbar (0.1 GPa) dynamically. The maximum lateral pressure is 1.5 kbar (0.15 GPa) statically or dynamically. The testing machiine can also be used to apply dynamic loading superimposed on a static preload. The static preload pressures can be as large as 0.2 kbar (0.02 GPa). The tunnel cavity is maintained at ambient pressure, with access at both ends for photography and electrical instrumentation. (Author)