Scientific and Technical Applications Forecast, 1964, Excavation

摘要

This study deals primarily with underground excavation in rock. Conventional tunnel driving techniques, that is by drilling blasting with explosives and loading, can produce 50 to 75 feet advance per day. There is little likelihood that this daily advance rate by these means will exceed a maximum of 100 feet per day in 20 years. At the normal industrial research and engineering development pace mechanical tunnel drivers will be able to penetrate from 100 to 200 feet per day in twenty years. An accelerated research program would reduce the time to reach this 20 year forecast to ten years and would provide a capability of 150 to 250 feet per day in 20 years. Research will involve a thorough study of rock mechanics to establish unique means of causing controlled massive failure of rock as well as research in mechanisms and techniques to accomplish these desired results. Nuclear devices do not show much promise for making usable underground cavities although they will undoubtedly be used to mine massive ore bodies with planned roof failures. On the other hand nuclear devices will be used for large scale surface excavations such as may be required for canal or harbor excavations.