Please use this identifier to cite or link to this item: https://hdl.handle.net/11681/5613
Title: Fundamental concepts for the rapid disengagement of frozen soil : phase 2
Authors: Foster-Miller Associates.
Keywords: Cold weather construction
Disengaging
Excavation
Fracturing
Frozen soils
Frozen ground
Permafrost
Relaxation (mechanics)
Tunneling (excavation)
Tunnels
Publisher: Cold Regions Research and Engineering Laboratory (U.S.)
Engineer Research and Development Center (U.S.)
Series/Report no.: Technical report (Cold Regions Research and Engineering Laboratory (U.S.)) ; 234.
Description: Technical Report
Abstract: A wide variety of novel disengagement processes which appeared promising as a result of the Phase 1 effort were investigated experimentally and analytically, including determination of the means by which they might be implemented as complete excavating system concepts. Mechanical processes, combined in an ingenious manner so as to optimize the overall effectiveness, are considered to offer the most satisfactory short-term answer to the permafrost disengagement problem. The most satisfactory primary processes include shear cutting and indentation cutting. Also satisfactory from an effectiveness standpoint is high-velocity liquid droplet impingement, but extensive development is required to advance the technology sufficiently to make it practical as a large-scale material disengagement device. Promising secondary processes include cantilever bending fracture, brittle ridge fracture and controlled explosive loading. Analysis of the various combinations of the promising primary and secondary processes resulted in three complete permafrost disengagement concepts; (a.) Penetration and brittle ridge fracture, (b.) Kerfing and cantilever fracture, (c.) Penetration and airblasting. No exceptional increases in energy effectiveness or rate of material disengagement are possible at the present time by using novel energy interactions, such as lasers and high-energy electron beams. Although some of these novel processes are satisfactory in terms of energy effectiveness, they present severe implementation problems within the existing state of the art.
URI: http://hdl.handle.net/11681/5613
Appears in Collections:CRREL Technical Report

Files in This Item:
File Description SizeFormat 
CRREL-Technical-Report-234.pdf13.59 MBAdobe PDFThumbnail
View/Open