Call number:
ZSP-201-81/17
In:
CRREL Report, 81-17
Description / Table of Contents:
Environmental conditions are described for the continental shelf of the western Arctic, and for the shelf of Labrador and Newfoundland. Special emphasis is given to the gouging of bottom sediments by ice pressure ridges and icebergs, and an approach to systematic risk analysis is outlined. Protection os subsea pipelines and cables by trenching and direct embedment is discussed, touching on burial depth, degree of protection, and environmental impact. Conventional land techniques can be adapted for trenching across the beach and through the shallows, but in deeper water special equipment is required. The devices discussed include hydraulic dredges, submarine dredges, plows, rippers, water jets, disc saws and wheel ditchers, ladder trenchers and chain saws, routers and slot millers, ladder dredges, vibratory and percussive machines, and blasting systems. Consideration is given to the relative merits of working with seabed vehicles, or alternatively with direct surface support from vessels or from the sea ice
Type of Medium:
Series available for loan
Pages:
38 Seiten
,
Illustrationen
Series Statement:
CRREL Report 81-17
URL:
https://hdl.handle.net/11681/9409
Language:
English
Note:
CONTENTS
Abstract
Preface
Introduction
The western Arctic of North America
The continental shelf of Newfoundland and Labrador
Burial depth for pipes and cables
Degree of protection offered by burial
Environmental impact
Trenching the beach and the shallows in the western Arctic
Trenching beyond the shallows
Suction, or hydraulic, dredging
Bottom-t raveling cutterhead dredges
Plows
Rippers
Water jets
Subsea disc saws and wheel ditchers
Subsea ladder trenchers and chain saws
Subsea routers and slot millers
Bucket ladder trenchers
Vibratory and percussive devices
Hard rock excavation under water
Control and monitoring of subsea machines
Vessels and vehicles
Trenching from the sea ice
Costs of subsea trenching
Reference
Appendix: Description of waters off Alaska and Newfoundland
Location:
AWI Archive
Branch Library:
AWI Library
