Article 1 — Description
Furnish and install linear drains of the sizes and descriptions shown on the plans as cast -in-place trench drain, precast trench drain, or slotted drain.
Article 2 — Materials
Provide materials in accordance with the following.
2.1 Cast -in-Place Trench Drain . Provide a trench with a slope as shown on the plans. Furnish forms capable of
maintaining proper alignment during the concrete placement. Ensure connections to structures do no t restrict the hydraulic flow of the trench drain. Use Class C concrete conforming to Item 421, “Hydraulic Cement Concrete. ” Provide grates and frames conforming to the requirements of DMS -4370 , “Precast Trench Drain.” Minimum plan dimensions for removable grates are 12 in. wide and 36 in. long. Grates with lesser dimensions must not be removable. Provide shop drawings sealed by a licensed professional engineer stating the trench drain system meets loading requirements . Submit documents showing design loadings if using a proprietary system. Furnish documentation in accordance with Section 471.2.3., “Documentation.”
2.2 Precast Trench Dr ains. Furnish precast trench drains from pre- approved manufacturers in accordance with
DMS -4370 . The Department’s MPL includes approved manufacturers and their products. Unapproved precast trench drains will not be accepted. Furnish materials conforming to the following where required. Item 420, “Concrete Substructures” Item 421, “Hydraulic Cement Concrete” ( Use Class C concrete unless otherwise shown on the plans. ) Item 440, “Reinforcement for Concrete”
2.3 Slotted Drains . Fabricate and furnish materials in accordance with Item 460, “Corrugated Metal Pipe.”
Furnish galvanized steel or aluminized steel (AASHTO M 36, Type 2) pipe with a minimum thickness of 16 gauge. Slotted drains consist of a drain guide assembly attached to a longitudinal opening in a corrugated metal pipe. Unless otherwise shown on the plans, fabricate slotted drains with bearing bars and crossbar spacers meeting the requirements of ASTM A36 welded to the longitudinal opening in the corrugated metal pipe. Galvanize the drain guide assembly after fabrication in accordance with Item 445, “Galvanizing.” Clean and repair welded areas and heat -affected zones in accordance wit h Section 445.3. 4., “Repairs.”
2.4 Slotted Drain Outfalls. Slotted drain outfalls consist of the corrugated metal pipe that connects the slotted drain to the main drainage line.
2.5 Backfill . Provide cement -stabilized backfill in accordance with Item 400, “Excavation and Backfill for
Structures,” or hi gh-slump, low -strength concrete with a minimum of 180 lb. of cement per cubic yard. 744 3. CONSTRUCTION OF CAST -IN-PLACE TRENCH DRAINS Perform excavation in accordance with Item 400. C onstruct trench with a slope as shown on the plans. Submit shop drawings that provide enough detail to ensure seamless installation of the trench drain adjacent to the proposed or existing pavement structure. If using a proprietary system , provide shop drawings that contain the manufacturer’s installation guidelines and any sequential order of construction. Construct the trench drain with a maximum allowable tolerance of ±1/16 in. for dimensional accuracy and rail co- planar ity. Provide a smooth finish on the surface of the t rench that will convey runoff. Make connections to new or existing structures as shown on the plans or as directed. Remove and dispose of trench drain forms properly. Install grates with retaining pins on each of the four corners. Remove all construction debris from the trench drain. Do not provide removable trench drain grates at any location where wheeled vehicles may drive over them , including roadway lanes, shoulders, and driveways. Remove all construction debris from the trench drain.
Article 4 — Construction of Precast Trench Drains
Place precast trench drains in concrete pavement or encased in a concrete grade beam and subgrade designed to support H-20 wheel loading. Perform excavation in accordance with Item 400. Construct trench with a slope as shown on the plans. Use interconnecting end profiles on adjoining channels to maintain channel alignment within ±1/16 in. Use non-sloping sections as show n on the plans or as directed. Assemble and install precast trench drains in conformance with approved shop drawings and manufacturer’s recommendations at the locations directed on the plans. Provide shop drawings containing the manufacturer’s installation guidelines. Encase precast trench drains, not cast in concrete pavement, in concrete grade beams, as shown on the plans and suitable to support the trench drain and retain the trench grate from pull out. Ensure the grade and alignment of the installed grates match the grade and alignment of the surrounding pavement. Do not provide removable trench drain grates at any location where wheeled vehicles may drive over them , including roadway lanes, shoulders, and driveways. Remove all construction debris from the trench drain.
Article 5 — Construction of Slotted Drains
Install slotted drains and slotted drain outfalls as shown on the plans and in accordance with the requirements of Item 460. Excavate and backfill in accordance with Item 400. B ackfill trenches as shown on the plans or as directed. Furnish slotted drains in 20-ft. lengths, minimizing the number of joints required.
Article 6 — Measurement
This Item will be measured by the foot, between the ends of the linear drain along the pavement surface as installed, complete and in place. Where inlets are included in lines of linear drain, that length of drain tying into the structure wall will be included for measurements, but no other portion of the structure length or width will be included . 745 7. PAYMENT 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 “Cast -in-Place Trench Drain,” “Pre cast Trench Drain (in Concrete Pavement) ,” “Pre cast Trench Drain ( Without Concrete Pavement) ,” or “Slotted Drain” of the size specified. This price is full compensation for structure excavation, installing the trench drain, concrete, reinforcing steel, reinforcement anchors, other connecting devices, furnishing all materials (including forms, rails, anchorages, support bars , and grates), tools, labor, equipment, and incidentals .