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George E. Wickham -Henry R. Tiedemann |
 USBM - Spokane Mining Research Center Improving the state-of-the-art of tunneling is a continuing challenge to those involved in underground construction. New methods and procedures are usually evolved over a relatively long period of time as compared to advancements in other types of construction. To a large extent this is probably due to the fact that tunneling deals with a material or medium - the rock structure - whose physical properties are not only extremely varied, but in many instances virtually unknown until time of penetration. This hovering of the unknown tends to make “non believers” of many and at best leads to a general reluctance of accepting new ideas or procedures. The situation is further complicated by: 1) discrepancies in terminology and respective meanings as used by different disciplines to describe, define or evaluate pertinent factors and the irrelative effect on the tunneling process and 2) the fact that no two tunneling situations are identical with respect to either geological conditions or construction and contractual requirements. . |
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