15-BU-017: Construct Robot Obstacle Confidence Course

Location: Naval Base Guam Apra Heights

Start: September 2015
Completed: April 2016

Scope of Work:

CONTRACTED SCOPE
Provide all necessary labor, material, transportation, supervision, equipment and other incidental work required for this project. 

Civil Work: Clear and grub course area, scarify existing grade 1′-0″ deep (min.) or as required and remove/dispose of unsuitable material, prepare grade, ready to receive backfill, as required to support new construction.

Structural/Architectural Work: Backfill with base course and compact, ready to receive reinforced concrete footing/foundation and reinforced concrete floor slab, construct reinforced footing/foundation, construct reinforced concrete masonry unit curb and walls in accordance with the attached notional sketch, construct reinforced concrete ramp with hardwood strip and stair with wooden treads from 2″ x 12″, all with 2″ dia. X 3′-6′ high safety railing, provide weed control fabric all throughout the area backfilled with 12″ (min.) gravel/sand mix and area enclosed by CMU curb, provide compacted sand/gravel ramp up to top of conc. curb at beginning and end of obstacle courses, grade to daylight all areas around and within the course area, slope to daylight at course perimeter shall be at least 1:4, and cleaning and disposal of construction debris, complete and ready for use. 

PROJECT NARRATIVE 
IAN ensured that all off-site fabricated and procured materials were confirmed on-island before the commencement of construction. These included metal fabrications, hardwood products, anchors, etc. This ensured that the work will be performed in the shortest duration possible, and thus providing minimal impact to ongoing activities in the EODMU-5 compound. A 6′ high perimeter chainlink fence with an opaque, breathable fabric and a a double lockable gate (10′ wide) was installed. A combination of pounded corner posts (including at gates) and movable panels were also installed. Temporary environmental controls were also placed, including storm-water pollution prevention  measures consisting of silt fence and hay bales and/pr silt sock; along with silt sack or silt fabric protection of nearby, downstream storm-water inlet structures where required. 

IAN envisioned utilizing larger excavation equipment for the site demolition and excavation for footings. Generally, equipment in the Caterpillar 315 to 320 class was utilized. This maximizes efficiency during the larger earth moving activity. Watering was also used on site during site demolition and excavation when necessary to limit the spread of dust and fine particles that could pose a nuisance to nearby personnel or ongoing activities.

After excavation is complete, the suitability of the existing sub-base material will be confirmed for structural bearing. The elevation of footings (with the help of professional suveyor) will be established and the sub-base grade will be adjusted with appropriate structural aggregate fill. 

During preparation of the sub-base for concrete footings, smaller machinery will be utilised for greater fine-tune control and less impact to nearby activities (i.e. noise, exhaust, etc) A mini or compact class of excavator is envisioned. 

The same small equipment was used during all backfilling and final ‘finish’ filling and dressing with gravel and hammermill mix, as required by the RFP. 

Forms were used will be smooth-faced and free of surface deformities and deleterious materials. Steel rebar was installed and inspected. Concrete was tested for temperature, slump, and compressive strength by a local materials testing firm. Only ready-mix concrete was used. Concrete was placed, vibrated, and finished. It was a wet-cured utilizing burlap to maintain moisture. Masonry structures did not bear on placed concrete until laboratory break strengths were achieved. 

The placement of curbs on top of masonry walls, ramps, and flat surfaces were similar. If desired, the top corners of curbs and edges of ramps were chamfered. Control joints and expansion joints were installed at intervals meeting code requirements and standard practice. Joints were sealed with silicon caulk. Flat/mag finish or broom finish was provuded on concrete surfaces as desired by NAVFAC’s CM team and/or the end-user. 

Careful attention to dimenstions from the final design documents and the use of a professional surveyor ensured that all dimensions were accurate prior to any placement of concrete or masonry. 

Masonry was set in level and plumb coursework. All required cuts were made with a wet diamond blade saw. Careful attention was paid to the consistency and moisture content of mortar when placed. Joints were carefully tooled for optimum long-term durability and appearance. Vibrating and/or the use of weep holes were used to ensure grout reaches and fills all cells. 

Metal guardrails and channels were fabricated and hot-dip galvanized off-island. IAN was aware of the need to have steel products fabricated to the exact dimensions required by the design documents so that no field cutting or drilling is required (thus disturbing the protected galvanized coating). IAN took every measure to ensure these dimensions are 100% firm before alloing for any fabrication to take place. 

Only skilled journemen carpenters were utilized for the hardwood carpentry work required at ramps (wood strips) and bridges. All wood work was consistent with respect to cut dimensions, straightness of cuts, and drilled holes.