Robertson Tunnel
General Information
| Structural Type: |
Tunnel
|
|---|---|
| Function / usage: |
Metro tunnel / subway tunnel
|
| Construction method: |
Tunnel boring machine (TBM)
Drilling and blasting |
| Other name(s): | West Hills MAX Tunnel |
| Built: | 1993 - 1996 |
| Status: | in use |
Geographic Information & Related Structures
| Location: |
Portland, Multnomah County, Oregon, USA, North America |
|---|---|
| Coordinates: | 45° 30' 38.00" N 122° 43' 1.00" W |
Technical Information
Dimensions
| diameter | 6.4 m | |
| length | 5 000 m | |
| depth | 24 - 91 m |
Chronology
| July 1993 | Construction begins at west portal of north tunnel. |
|---|---|
| August 1994 | Boring begins at east portal of north tunnel. |
| 29 December 1995 | North tunnels meet after 16 months or driving the tube. |
| April 1996 | South tunnel boring begins. |
| 15 August 1996 | South tunnels meet after only 4 months. |
| 12 September 1998 | The tunnel is placed into service. |
Notes
Tunneling was hampered by unexpected loose layers of silt and gravel, and crumbling basalt which prevented the custom boring machine from working effectively.
Participants
Currently there is no information available about persons or companies having participated in this project.
Relevant Web Sites
Relevant Publications
There is no relevant literature listed in the database.
Internal Information
| Structure-ID: | s0059831 |
|---|---|
| Created: | 06/04/2011 |
| Last Updated: | 05/03/2013 |