Base and Drainage Construction

Base and Drainage Construction

1. The sub-base will have a slope of 0.5%.
2. The base aggregate shall consist of a minimum of four inches (4”), free-draining stone, depending on site location. Finish slope of porous aggregate should be 0.05% from the centerline of the field to the sidelines, and the grade should not vary more than a half an inch (1/2”) in ten feet (10’). The sieve analysis of the open grade stone shall show a gradation as follows:
% of Passing Sieve Size
100 1.25”
70-100 3/4”
30-50 3/8”
8-40 #4
0-12 #16
0-5 #200

The Stone shall be installed maintaining a finished grade slope of 0.5%. The owner and Synthetic Turf System Manufacturer must approve variations of this finished slope. The depth of the aggregate will increase at the edges of the field, as determined by the sub-base slope, as the elevations are maintained throughout. The washed stone aggregate material must be free draining, consistent with the vertical draining requirements of the Synthetic Turf System Manufacturer and owner.
3. The finished grade of the aggregate base shall not vary more than a quarter of an inch (1/4”) in ten feet (10’). A laser grader is to be employed.
4. Cut and fill of sub-base soils should be conducted as necessary to establish proper grade of sub-base to a tolerance of one-half inch (1/2”) in ten feet (10’). Sub-base shall be sloped of 0.5% from center of field toward sidelines.
5. The sub-base compacted using a ten (10) ton vibrating roller, to approximately 95% Proctor density.
6. Vendor will supply and install a porous non-woven polypropylene stabilization fabric (Amoco 4545 or equal) over the entire surface before the installation of the stone depending on geographic location.
7. Install a one inch by six inch (1” x 6”) prefabricated Multi-Flow (or equal) under drain system in a “V” deign as shown on drawing with lines approximately twenty feet (20’) on center and connect to a perimeter linear drain.
8. The Contractor shall supply water proof tape and all necessary connectors, per subsurface drainage system manufacturer’s recommendation, and is responsible for a proper and secure connection between all new and existing drainage lines.
9. Install up to a two-inch (2”) layer of one eighth to a quarter of an inch (1/8” – 1/4”) porous stone over the base, maintaining slope and grade, depending on the geographic location. Finish grade to tolerance of a quarter of an inch (1/4”) in ten feet (10’) and compact with four to six ton (4 – 6) motorized roller to approximately 90% Proctor. The sieve analysis of the fine grade stone shall show a gradation as follows:
% of Passing Sieve Size
100 1/4”
60-100 1/8”
5-10 #100
0-5 #200

10. The Synthetic Turf System Manufacturer and architect will accept the aggregate base in writing prior to the installation of the Synthetic Turf System.

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