Image displays a typical micropile installation
Treadwell & Rollo is currently performing Quality Control services while observing micropile installation and testing for the BART Earthquake Safety Program, North Oakland Aerial Structures.
Micropiles are being installed to resist uplift loads due to seismic forces created during an earthquake. A typical micropile consists of 10-inch diameter, drilled, grout-filled shafts with steel bars embedded in the grout. The micropiles develop their uplift resistance from friction between the perimeter of the shaft and the surrounding soil.
Geo Grout, Inc. is scheduled to install a total of 757 micropiles around multiple railway overpass foundation elements for the BART North Oakland Aerial Structures. The North Oakland portion of aerial structures being seismically upgraded runs between the east and westbound lanes of the Highway 980/24 corridor between 29th Street, close to downtown, to Patton Street, located in the Rockridge area.
Map of North Oakland Aerial BART Structures that are part of this project
Our team includes Project Manager Antonio Mencarini, EIT, Senior Staff Technician Ron Reindl, Project Engineer Lisa Splitter, PE, and Staff Engineers Kristen Lease, EIT, LEED AP, and Rachael Severn, EIT. As part of our assignment we are observing and documenting all micropile drilling and installation procedures and are in daily communication with the BART project team.
The BART Seismic Retrofit Project is scheduled for completion in late 2010 and is expected to cost approximately $33.5 Million.
I’m a sucker for anything vintage or retro. This is just too cool.
Fascinating stuff. For even more info on seismic retrofitting and how it works go here:
http://bayarearetrofit.com/how_retrofitworks3.html
Thanks
Howard Cook