Purpose

To consolidate, disseminate, and gather information concerning the 710 expansion into our San Rafael neighborhood and into our surrounding neighborhoods. If you have an item that you would like posted on this blog, please e-mail the item to Peggy Drouet at pdrouet@earthlink.net

Thursday, March 5, 2015

Bertha ready for disassembly and repair

http://www.tunneltalk.com/Seattle-Alasskan-Way-04March2015-Bertha-ready-for-disassembly-and-repair.php

March 4, 2015


  Bertha in the recovery shaft



Bertha has moved forward a total of 57ft since resuming her short drive on February 17. In that period the 17.5m diameter machine has completed nine permanent concrete tunnel rings.

With Bertha now in position, crews have begun the challenging task of disassembling the world’s largest tunneling machine. They will move through a number of methodical steps as they prepare to lift four pieces weighing up to 2,000 tonne to the surface for repairs.

According to WSDOT completion of the repair – which involves replacement of the damaged bearing seals and the fitting of a brand new new main bearing as a precautionary measure – will take “weeks”.

References