The station’s mezzanine level and platform are located under 4th Street between Folsom and Howard.  Here, workers finish construction of the mezzanine level’s floor slab.

On the surface near 4th and Howard, workers are excavating and reinforcing a trench to install new utilities.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

Workers assemble rebar cages for mezzanine floor beams by hand.

A closer view of the rebar work. To the right, a worker signals fellow team members as they work in the station box.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!

Workers install a high pressure water line at 4th Street and Howard Street

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.

The Central Subway Team

After demolishing a portion of this wall, the former southeast corner of the Union Square Garage is connected to the north concourse

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Construction is progressing in the Union Square|Market Street station. Crews have broken through part of a wall to connect the north concourse to the former southeast corner of the Union Square Garage. Work is also being done to restore a portion of the sidewalk and curb at the northeast corner of Stockton Street and Geary Street. On O’Farrell Street, compensation grouting is being performed in preparation of roof deck panel installation. Excavation continues both at street level and below the ground.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.

The Central Subway Team

Sections of pipe are stacked for installation on 4th Street north of Townsend

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Construction at the Yerba Buena|Moscone station continues. Construction of the mezzanine floor is progressing and crews are building concrete forms for the final section. Excavation continues in the headhouse. Workers are installing a water line at 4^th Street and Howard.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.

The Central Subway Team

Restoration of the sidewalk, curb and street at Stockton and Geary Street

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Construction moves forward for Chinatown. Sewer slip lining is near completion. Excavation of the station continues. Other activities include north access shaft construction and utility relocation.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.

The Central Subway Team

]]> http://www.centralsubwayblog.com/blog/2016/04/project-advancement-april-29-may-9/feed/ 0 http://www.centralsubwayblog.com/blog/2016/04/2016-station-construction-update/ http://www.centralsubwayblog.com/blog/2016/04/2016-station-construction-update/#respond Tue, 26 Apr 2016 20:14:18 +0000 http://www.centralsubwayblog.com/blog/?p=7486 Here’s what you can expect to see as construction progresses along the Central Subway alignment.

4^th and Brannan Station

Construction for the 4^th and Brannan Station is progressing, and activity along the surface portion of the alignment will continue on 4^th Street from Bryant to King. Utility work is expected to continue through 2016. The crew is working on a high pressure auxiliary water supply system on 4^th between Brannan and Townsend. Two sewer lines will be installed on the east side of 4^th and another will be reconstructed between Townsend and King.

To power the trains, an Overhead Catenary System (OCS) needs to be installed between Harrison Street and King Street. Installation of the OCS has three components: foundations, poles and wires. The foundations currently being installed are the bases for the poles. Once these are constructed, the poles will be mounted later in the year. The last step is the connection of electrical wires. These wires provide power to Muni’s light rail vehicles. The OCS work is expected to be completed in early 2017.

In the fourth quarter, crews are expected to begin trackwork and infrastructure installation in the tunnel.

Utility work continues on 4th Street

Yerba Buena|Moscone Station

At Yerba Buena|Moscone, crews will be focusing on building the interior levels of the station box. The contractor will continue to excavate downward inside the station box from the mezzanine level to the concourse level. In the headhouse, crews will complete excavation and construct internal walls upward through the concourse, mezzanine and surface levels.

Most of the construction activity for the station is conducted underground. The mezzanine is under construction and is expected to be completed by June. Installation of steel supports is underway in the station box and the headhouse. Construction of the station box walls and flooring is anticipated to begin in the fourth quarter.

By December, it is expected that all four travel lanes will be open on 4^th Street between Howard Street and Folsom.

Workers clean slurry walls before building internal walls

Union Square|Market Street Station

For the Union Square|Market Street site, excavation is ongoing. Beneath Stockton Street between Geary and O’Farrell, excavation of the station box progresses. Excavation is being performed on O’Farrell Street  in order to install the final roof deck panels.

The demolition and restoration of the southeast corner of the Union Square Garage is underway. This area will become the north station entrance at Geary and Stockton. A portion of the garage wall will be demolished which will connect the entrance with the north concourse of the station.

Jet and compensation grouting are being performed on Stockton Street from Maiden Lane to Ellis Street. Jet grouting limits ground water from seeping into the station. Compensation grouting provides stability to the foundations of surrounding structures of the station.

Utility work continues at Geary Street and Maiden Lane.

Roof deck panels are being installed on Stockton Street and Geary Street

Chinatown Station

In Chinatown, crews are excavating the north access shaft beneath Stockton Street between Washington and Jackson. This shaft will become an emergency exit stairwell for the station. Temporary steel supports have been installed in the headhouse to prepare for the next phase of excavation.

At the arched entrance way, crews are injecting grout to harden the soil where excavation will begin. This work reinforces the structure of the station. After the entrance way is excavated, “shotcrete,” a fibrous concrete material, will be sprayed onto the walls for stability. Excavation, waterproofing and rebar installation will continue through 2016.

A view of the archway entrance to the future station cavern

Utility work is performed in a trench on 4th Street

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Construction of the Union Square|Market Street station is progressing. The demolition of the southeast corner of the Union Square Garage is nearly complete. Remodeling of the north station entrance is underway. Jet and compensation grouting are being performed on Stockton Street from Geary Street to Ellis Street. Roof deck panel installation is progressing on O’Farrell Street. Excavation continues at street level and below.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.

The Central Subway Team

Construction of the Yerba Buena|Moscone Station mezzanine floor is underway

This notice provides a construction update and a look ahead for what to expect in the areas where we are building four new stations along the alignment. You’ll find information about work activities, traffic and transportation impacts taking place over the next two weeks at SoMa, Yerba Buena|Moscone, Union Square and Chinatown.

Installation of 36” and 48” sewer lines on the east side of 4th Street between Bryant Street and King Street begins on Monday, April 18. Hours of construction are 7a.m. to 4p.m. Two lanes of traffic will be open on the west side of 4^th Street. Parking will be restricted on both sides of 4^th Street.

Construction schedules, bus routes, and stop locations are subject to change due to unforeseen conditions. Signs will be posted at affected stops to advise of service changes.

Our thanks go out to the businesses, residents, shoppers, commuters, and all those who are touched by the Project, for their continued engagement as we work to extend the city’s public transportation system.
The Central Subway Team

Here is a look at the work taking place underground, where construction crew members mix materials for the next phase of mezzanine floor slab construction.

An up close photo of a carpenter as he cuts wood for the next section of the station box.

If you would like to see more photos of project construction, check out our Flickr, updated weekly!