NR/L3/CIV/006/4D ISSUE 1
Handbook for the Examination of Structures Part 4D: Unlined Tunnel Geotechnical Risk Assessment Guidance
inactive
| Organization: | NR |
| Publication Date: | 1 September 2009 |
| Status: | inactive |
| Page Count: | 41 |
scope:
An UTGRA applies to existing:
- full profile unlined Tunnel Section lengths;
- unlined Shafts;
- natural rock Portals.
This part of the handbook may also be applied to unlined sidewalls, unlined Adits, unlined Cross Passages and unlined Headings.
Purpose
This part of the handbook describes a standard method of evaluation of unlined Tunnels using the rock mass risk assessment system.
The assessment evaluates the risks of instability resulting from the condition of the unlined Tunnel, and is termed the Unlined Tunnels Geotechnical Risk Assessment (UTGRA).
Document History
September 7, 2019
Structures, Tunnels and Operational Property Examinations: Unlined Tunnel Geotechnical Risk Assessment (UTGRA)
An Unlined Tunnel Geotechnical Risk Assessment (UTGRA) is carried out to identify geological features or geotechnical issues which may affect the stability of an unlined Tunnel.
This module...
NR/L3/CIV/006/4D ISSUE 1
September 1, 2009
Handbook for the Examination of Structures Part 4D: Unlined Tunnel Geotechnical Risk Assessment Guidance
An UTGRA applies to existing:
full profile unlined Tunnel Section lengths;
unlined Shafts;
natural rock Portals.
This part of the handbook may also be applied to unlined sidewalls, unlined Adits,...