- 881 - SECTION 1043 -- FLAP GATES
1043.01 Description
1.Flap gates shall be a double-hinged type furnished in accordance with the dimensions shown in the contract. The gates approved for use shall be furnished with seats and anchor dev ices or be factory mounted on the corrugated metal pipe.
1043.02 Material Characteristics
1.The gates shall consist of a fl ap and a seat with a circular opening of the size shown in the contract. The flaps and seats shall be designed to withstand the maximum hydraulic head above the centerline of the gate.
2.The gates shall be designed to open and close under a differential head of 0.2 foot (61 mm) and shall provide a watertight seat against backflow.
3.The cast iron gates shall be m anufactured in accordance with the requirements of ASTM A 126 Class B.
4.Any devices necessary to fasten the gate to the culvert pipe must be approved by the Engineer.
1043.03 Acceptance Requirements
1.Flap gates approved for use are shown in the contract. - 882 - SECTION 1044 -- BAR GRATES FOR FLARED END SECTIONS
1044.01 Description
1.This Specification covers bar grates for use with metal and reinforced concrete flared-end sections.
1044.02 Material Characteristics
1.Bar grates shall be constructed as described in the contract. Bar grates shall be fabricated from plates and round smooth bars complying with the requirements of ASTM A 36/ A 36M or ASTM A 575, Grade 1020.
2.Coatings a . P a i n t
1.Two separate coats of paint shall be applied to the grates in accordance with Section 709.
2.The first coat shall be inorganic zinc-silicate primer. (3) The second coat shall be brown or beige paint. (4) All painting may be done in the shop.
5.All paint shall comply with the requirements of Section 1077.
b.TGIC Polyester Coating (1) Acceptable coating materials are on the Department’s Approved Products List.
2.Apply the coating as recommended by the manufacturer (3 mil (76 m) minimum).
c.Galvanized (1) Hot-dip galvanized in accordance with ASTM A 123.
1044.03 Acceptance Requirements
1.Bar grates will be accepted on t he basis of a fabric ator’s certificate showing compliance with these Specifications.
Source: Nebraska Standard Specifications for Highway Construction, 2017 Edition. Pages 915–915 of 1,048.