11-BU-008: Replace Tower Foundations

Customer: DZSP21

Location: RB-52, Radio Barrigada

Start: October 2011

Complete: June 2012

Awarded: 2012 GCA Excellence in Construction Merit Award

Scope of Work: Remove and dispose concrete peripheral guy anchors. Backfill & compact peripheral guy anchor holes.Excavate, remove and dispose concrete tower guy anchors. Remove and dispose concrete tower base foundation. Auger holes for peripheral guy anchors, 12” wide by 3 ft deep.

Install cylindrical formwork over each peripheral guy anchor hole, 12” diameter, with upper edge adjusted so that all anchor tops are at the same elevation. Place 3000 psi concrete to form each peripheral guy anchor with customer supplied anchor eye embedded at center. At existing holes for tower guy anchors, install 4 each #6 rebar, 24 LF, and 6 each #4 rebar, 42 LF, bent and wired in box layout. Place 3000 psi concrete to form each tower guy anchor with customer supplied anchor eye installed at 45 deg from vertical and embedded at center.

Backfill and compact tower guy anchor excavation. At existing hole for antenna base foundation, install 4 each #4 rebar, 12 LF, and 8 each #6 rebar, 24 LF, bent and wired in box layout. Place 3000 psi concrete to form antenna base foundation with customer supplied antenna tower pin embedded at center. Install new customer supplied ground screen wire in a perimeter circle centered on antenna base foundation, 164 ft diameter, approximately 5100 LF, buried 6” deep. Install new customer supplied ground screen wire in a radial pattern from perimeter wire to antenna base foundation, spaced 6 deg apart, 85 LF each, approximately 5100 LF total, buried 6” deep and soldered to perimeter wire. Place top soil and seed disturbed ground.