Scanned Acoustical Holography for Geological Prediction in Advanced of Rapid Underground Excavation. Phase I.

摘要

In order to make underground space utilization a viable alternative to surface utilization,an intensive effort is underway to examine the factors involved in underground excavation and determine these factors can be affected to improve productivity. A high priority for improving productivity is the development of geological techniques for determining rock and groundwater conditions prior to excavation. This program was to demonstrate the use of acoustical holography methods to detect and image targets in a volume of rock,and to show how the existing system of rectilinear scanned holography could be so modified to be most efficient and most compatible for 'real-time'use in a tunnel with a tunnel boring machine. The primary goal of Phase I is to demonstrate holographic imaging of programmed targets in a volume of rock using rectilinear and circular scanning systems.