Phoenix Project #2103
This project called for the installation of five (5) drilled micropiles (“DMPs”) to support new foundations as part of renovations to the existing MIT Burton Conner Dormitory.
In advance of production work, Phoenix met with the project team several times to develop a work plan to ensure no logistics were overlooked when mobilizing into the very small work zone. Mobilization into the building required partial disassembly of the drill rig followed by reassembly once into position. This process was required to gain access at multiple pile locations and required a great deal of time and effort on site to implement safely.
Once inside the building, Phoenix had to walk equipment through existing doorways and install the piles in under nine (9) feet of headroom and within 12 inches of existing walls and columns. We also had to recycle drill spoils with the use of open-top tanks. These tanks were strategically placed along the perimeter of the building to allow for other construction activities to continue.
The piles were drilled using a limited-access, track-mounted drill rig, advancing 2.5 foot long sections of drill casing to the design drill depths as much as 130 feet below working elevation. After reaching design tip elevation, a majority of the drill casing was extracted, one 2.5 foot long section at a time, to expose bonded lengths of up to 75 feet per pile. Several manmade obstructions were encountered that impacted the installations.
Despite the many challenges faced, all piles were successfully installed, cut off, and incorporated into the new foundation.