November 30, 2015
The boring machine is nearly as long as the pit! It is undergoing maintenance before being relaunched to bore the final tunnel to Husky stadium.
November 6, 2015
The first of two tunnel boring machines (TBM) arrives after tunneling from the Roosevelt Station site. The construction crew nicknamed this machine “Brenda” for reasons that aren’t entirely clear. You can get more information from the official web siteĀ http://www.soundtransit.org/northgatelink .
The north end of the station site.
Close-up of the north end of the station site.
The assembled dignitaries and journalists.
The cutterhead of the TBM is not yet visible.
An excavator with a hydraulic breaker chipping away the pit concrete wall.
The first sign of the TBM is dirt falling out from the hole.
There is the cutterhead!
Another angle on the cutterhead.
Breakout!
A worker spraying water to keep the dust down.
A flying mini-excavator.
This would be hard to do without a crane.
The excavator deposited into the station pit.
The south end of the station pit.
Descending into the station pit.
That’s a long staircase down to the bottom.
Frost built up on the soil freezing piping.
October 16, 2015
The excavation has been completed and a concrete base poured into the station box pit.
February 13, 2015
The station box pit is now deep enough that a conveyor belt is the most efficient way to remove the dirt.
October and November 2014
The digging and site preparation continue into the fall of 2014.
The north end of the station box pit.
The north end of the station box pit.
Pushing dirt
The south end of the station box pit.
The south end of the station box pit.
The south end of the station box pit.
The south end of the station box pit.
Compressor delivery by airmail.
The north end of the station box pit.
The north end of the station box pit.
A drill boring a hole for a soil anchor.
A drill boring a hole for a soil anchor.
Building a bridge over the south end of the station box pit.
Building a bridge over the south end of the station box pit.
Building a bridge over the south end of the station box pit.
September 2014
Excavation of the light rail station box pit started slowly as the foundations of the demolished buildings had to be removed.
Excavation is starting. This is the north end of the pit.
The crane operator looking up at the load.
Digging while disassembling foundations.
There were eight excavators of various sizes working in the hole.
A beautiful blue day in September.
One of two excavators filling dump trucks.
One excavator with a hammer broke apart the concrete foundations while a second with a “thumb” separated the steel, concrete and wood from the dirt.
The people look pretty small surrounded by all of this huge machinery!
The south end of the pit.
A week later, the first two struts have been placed across the pit.
The blue crane has moved to the other end of the pit.
The south end is a bit deeper now.
The operator inspecting the crane.
A tie-back drilling machine.
Tie-backs in place and ready to tension.
Did someone drop something?
A jog in the perimeter of the hole.
A utility vault takes shape.
More dump truck filling.
April through July 2014
The station box excavation uses two different retaining wall configurations. The east and west walls used steel H-beam caissons lowered into bored holes. The pit was excavated to a depth of 90 feet. The caissons are 120 feet long with holes bored that deep. The bottom 30 feet are filled with concrete to provide a foundation for the caissons. The space between the caissons was filled with wooden timbers known as lagging. The north and south walls used bored holes filled with rebar and/or steel H beams and concrete. The areas where the light rail tunnels will be located used fiberglass rebar as reinforcing.
Moving the hydraulic jacking fixture.
Moving the hydraulic jacking fixture.
Moving the jacking fixture.
Workers cleaning the concrete pumping machine.
The boring rig at work.
Boring the retaining wall holes behind the Neptune theater.
The south end of the site being prepared for retaining wall boring.
Utility relocation underway.
Another view of the underground utility relocation.
A worker is measuring the depth of the trench being dug by the excavator.
A second boring rig at work in front of University Manor.
This is a simpler boring rig; it lacks the device to place steel casings.
A worker is measuring the depth of the hole by dropping a weighted steel tape measure into it.
The auger being lowered into the hole.
A view north up Brooklyn Ave.
April 21, 2014
A chiller is one of the major components of a large building’s HVAC system. The UW Tower, a 22 story building constructed in 1974, needed to have its old chiller machinery replaced. The chiller is on the roof. It requires a rather ginormous crane to lift heavy machinery to the roof of a 22 story building. The best time to do this was when the adjacent lot had been cleared to make way for the light rail station.
The crane arrives on site.
A smaller crane is assembling the large crane.
Assembly continues.
Attaching the jib to the boom.
The jib assembled and ready to hoist.
There is an arm that supports the jib. Here it is extended out.
The main boom raised but not yet extended. It is a telescoping boom.
Close up of the crane carriage. The entire weight of the crane plus load is supported by and balanced by four outriggers.
On the left is part of the new chiller being hoisted up.
The old chiller components are sitting on the flatbed trailers.
Yup, that’s one big crane, 23 stories tall.
The jib atop the boom which extends the crane’s reach another 150 feet or so.
The lower part of the crane.
The crane after the lift has been completed.
Disassembly after a job well done.
Time to go home.
Some of the above photos, those labeled “SoundTransit_20140421xxxxx”, were taken by the Sound Transit web cam atop the Neptune theater.
January and February 2014
After the building demolition the site was graded and covered in asphalt. A large vertical boring machine was assembled to start drilling the holes for the caissons and pilings that would provide support for the walls of the excavation.
A large crawler crane is assisting with the assembly of the boring rig.
A smaller crane placing the mast on the boring rig.
The north end of the site before boring has started.
Boring on the east side of the site.
The intersection of Brooklyn and 43rd.
The old house on the corner is gone, replaced by a runoff water treatment facility.
The crane is holding a concrete pumping pipe into a bore hole.
Close up of a bore hole being filled with concrete. A rebar cage has already been placed into the bore hole.
A cement mixer truck filling a concrete pumping machine.
There was a hole in the NE corner of the site that I’m guessing contained a fuel oil tank which required cleaning the area out.
A view from 43rd Avenue looking north with the boring rig in the foreground
A view from the corner of 43rd and Brooklyn.
A shot taken from in front of the Cedars of Lebanon restaurant.
Looking north on Brooklyn before the construction wall was erected.
May through June 2013
The buildings on the site were removed to make way for the light rail station.
A long-armed excavator with a “nibbler” attachment severs steel beams like they were paper.
A second excavator takes the refuse and neatly stacks it into recyclable and non-recyclable piles.
Not much left of the bank.
The concrete box is the bank vault. Its thick concrete walls soon yielded to the hydraulic breaker.
There was a lot of rebar in that vault. It all got hauled off to be recycled.
The former UW building didn’t take long to demolish.
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A photographic archive of some recent UW construction projects