Category:614 Drainage Fittings (Grate Inlets)

Two types of inlet grates are shown in the standard plans. The curved vane grate (Standard Plan 614.11) is used in roadway and shoulder applications and is considered bicycle safe. The parallel bar grate (Standard Plan 614.10) may be used only in areas outside the roadway and shoulders, such as in grassy medians or other unpaved areas.

Standard curved vane grate inlets are 2 ft. (610 mm) long (measured in the direction of flow), and either 2 or 4 ft. (610 or 1219 mm) wide (measured perpendicular to the direction of flow). Only 2 ft. (610 mm) wide inlets may be used in curb and gutter sections; whereas 2 or 4 ft. widths may be used with integral curb (triangular) sections. Details of the inlet grates and gutter cross-sections may be found in the standard plans.

Grate inlets fit in Type S-1, S-2 or S-3 precast drop inlets. Precast drop inlet covers, Types A, B, C, D and E, are shown in the standard plans.

Hydraulic aspects of grate inlets are presented in 640.1 Pavement and Bridge Deck Drainage.

614.1 Construction Inspection Guidelines for Sec 614

Manhole Frame And Cover And Curb Inlet (for Sec 614.30). The Standard Plans are clear.

614.2 Laboratory Testing Guidelines for Sec 614

This article establishes procedures for Laboratory testing and reporting samples of grates, bearing plates, bolts, nuts and washers. No Laboratory tests are required for automatic floodgates, manhole frames and covers or curb inlets.

614.2.1 Procedure

Grates and bearing plates shall be tested for weight (mass) of zinc coating according to AASHTO M111. Bolts, nuts and washers shall be tested for weight (mass) of zinc coating according to AASHTO M232. Refer to Field determination of weight (mass) of coating for additional information concerning the testing of bolts, nuts, and washers for weight (mass) of zinc coating. All test data and calculations shall be recorded in Laboratory workbooks. Test results shall then be recorded through SiteManager.

614.2.2 Sample Record

The sample record shall be completed in SiteManager as described in Automation Sec 3510 and shall indicate acceptance, qualified acceptance or rejection. Appropriate remarks, as described in 106.9 Reporting Test Results, are to be included in the remarks to clarify conditions of acceptance or rejection. Test results shall be reported on the appropriate templates under the Tests tab.