Tunneling machine’s front end bolted in place

Bertha TBM cutterhead being lowered back into access shaft

Bertha TBM cutterhead being lowered back into access shaft

The troubled Alaska Way Viaduct Replacement Tunnel TBM known as Bertha has reached a milestone in its repair. The front cutterhead has been repaired, and has been lowered back into the access shaft to be re-attached to the TBM. The time-lapse video below shows the cutterhead being lowered down into the access shaft. What caught my eye was the number of steel cables on the crane blocks…that’s a heavy lift!

Time Lapse Video

[Source: WSDOT Alaskan Way Viaduct Project Page. Image: WSDOT]