UID:
kobvindex_GFZ20201117141920
Format:
iv, 14 Seiten
,
Illustrationen
Series Statement:
Research report / Cold Regions Research and Engineering Laboratory 30
Content:
Summary: Deformations occurring in a tunnel, two trenches, and a 30 m deep pit excavated in the Greenland névé in the summer of 1954 have been measured over a period of 2 years. The experimental results indicate that closure rates increase with lateral distance from a restraining boundary up to distances of about 1 m. At larger distances, the effect of the boundary is not appreciable. Closure rates for deep excavations are not found to be strongly depth-dependent. This is due to a roughly parallel increase of viscosity and pressure with depth. Vertical compaction results from the pit agree well with those calculated from the depth-density relation using Sorge's Law. A theoretical calculation for the tunnel and pit closure, which is a modification of existing theories for the deformation of an elastic, compressible, thick-walled cylinder, is in fair agreement with the observed deformations. From this agreement it appears that the flow behavior of the névé can be described on the basis of a Newtonian viscosity. The trench closure is described as the-squeezing out of horizontal layers, fixed at some distance from the trench, and modified only slightly by the drag of neighboring layers. Measurements will be continued during future summers.
Note:
CONTENTS
Preface
Summary
Introduction
Measurements and results
Tunnel
North-south trench
East-west trench
Deep pit
Theoretical development
Sorge's Law
Deformation of acylindrical tunnel in a viscous compressible medium
Discussion
Tunnel
Trenches
Deep pit
References
Appendix
In:
Research report / Cold Regions Research and Engineering Laboratory, 30
Language:
English
Keywords:
Forschungsbericht
URL:
https://hdl.handle.net/11681/2693
