Article 1 — Description
Furnish and install frames, grates, rings , and covers for inlets, manholes, and other structures .
Article 2 — Materials
2.1 Frame, Grate, Ring, and Cover Castings. Provide clean castings as shown on the plans. Ensure all gray
and ductile iron castings conform to the AASHTO Designation M 306. Cast or machine the bearing surfaces for traffic service castings between manhole rings and covers and between grates and frames with such precision as to prevent rocking. Provide gray iron castings in accordance with ASTM A48 Class 35B and AASHTO M 306 f or traffic service applications unless otherwise specified. Provide gray iron castings in accordance with ASTM A48 Class 35B for sidewalk or pedestrian applications unless otherwise specified. Provide ductile iron castings in accordance with ASTM A536, Grade 70- 50-05, unless otherwise specified. Provide steel castings in accordance with ASTM A27, Grade 70- 36, unless otherwise specified. Ensure all traffic service castings and gratings meet or exceed the H20 proof -load requirements of AASHTO M 306. Load test results and material certifications must be made available upon request. Ensure all traffic service (heavy -duty) rated castings and grating meet the proof -load testing requirements of AASHTO M 306. Ensure all load tests are conducted using a calibrated NIST -certified load cell. Ensure materials are loaded with a 9 × 9- in. load block to an applied load of 40,000 lb. for 1 min. without deformation or failure. Load test results and material certifications must be made available upon request. Provide castings within ±1/16 in. per foot of plan dimensions, and within ± 5% of plan weight.
2.2 Welded Steel Grates and Frames. Provide welded steel grates and frames as an assembly as shown on
the plans. Fabricate these assemblies in accordance with Item 441, “Steel Structures.” Use steel that m eets ASTM A36 or equivalent.
2.3 Documentation . Furnish a manufacturer’s certification stating the casting meets the proof -load testing
requirements of AASHTO M 306 f or traffic service castings.
Article 3 — Construction
Construct and install frames, grates, rings, and covers as shown on the plans. Weld in accordance with Item 448, “Structural Field Welding.” Tack weld grates and covers to the frame or ring when directed. Galvanize steel castings , welded steel grates , and frames in accordance with Item 445, “Galvanizing.” Galvanizing is not required for iron castings unless used in conjunction with structural steel shapes or shown on the plans. Provide galvanized bolts and nuts in accordance with Item 445.
Article 4 — Measurement
Frames, grates, rings, and covers, when a part of the complete manhole or inlet, will not be measured for payment directly, but will be subsidiary to Item 465, “Junction Boxes, Manholes , and Inlets.” Frames, grates, 740 rings, and covers, when not a part of a “ Manhole ( Complete) ” or “Inlet ( Complete), ” will be measured by the each.
Article 5 — Payment
When payment is required, the work performed and materials furnished in accordance with this Item and measured as provided under “Measurement” will be paid for at the unit price bid for “Grate,” “Frame,” “Grate and Frame,” “Frame and Cover,” or “Ring and Cover” with the type and number of grates specified, if necessary. This price is full compensation for equipment, materials, labor, tools, and incidentals .