UNAVCO PBO GPS Deep Drilled Braced Monument Installation Driller Instructions (2005)
GPS Deep Drilled Braced Monument Installation: Driller Instructions
The deep drilled braced GPS monument (UNAVCO DDBM*) is designed to create a highly rigid and immobile structure isolated from surface soil movement and cemented in place at depth. The monument consists of 5 legs (stainless steel pipes) placed into drilled holes, and welded together above the surface to create a "tripod" frame. Of the 5 legs, the center leg is vertical and the 4 other legs are installed at angles to brace the vertical leg.
The Plate Boundary Observatory (PBO) project will require the installation of at least 600 of these DDBM monuments throughout the Western US and Alaska. We hope to locate a small number of highly skilled contractors throughout the Western US and Alaska to install these monuments during the next five years. This scope of work is for a one-time installation project consisting of a small number (1-5) of these installations. This will allow us to evaluate the contractor for possible future work within PBO. Please provide a quote for services based upon the scope of work outlined below.
* Modified from the original SCIGN DDBM design of Duncan Agnew and Frank Wyatt.
[See attached .pdf file for more.]