EROSION CONTROL MAT 228.04
228.01 Description
This work consists of providing and installing erosion control mat for lining ditches and protecting slopes.
228.02 Materials
Provide materials in accordance with the following subsections: Material: Subsection: Erosion Control Mat 735.04.F Seed 735.03 Mat Fasteners 735.05.B
228.03 Equipment – Vacant
228.04 Construction Methods
A.Placing Mat
1.Ditch and Slope Preparation Grade, shape, and finish ditch and slope surfaces before installing erosion control mat so that they are stable, firm, and free of rocks or obstructions that would puncture the mat or prevent it from directly contacting the ditch and slope surface.
2.Ditches Observe the planting seasons indicated. Apply the sprig, or seed indicated to the ditch surfaces before installing the mat. Uniformly distribute g rass seed at a rate of 6 lb per acre [6.7 kg per ha] on the exposed soil before installing the mat. Distribute the seed in accordance with Subsection 232.04.B(1), "Seeding Method A – Hydraulic Seeder Method," or Subsection 232.04.B(4), "Hand Broadcasting Method." Use three rows of mat for the standard ditch placement. Place the first row in the centerline of the ditch, then place the two side rows adjacent to the first on th e ditch slopes, using lap joints of at least 3 in [75 mm]. Dig an anchor slot transverse to the ditch centerline at least 12 in [300 mm] vertically into the soil at the terminal ends of the ditch, secure the mat in the anchor slot with fasteners, backfill the anchor slot with soil, and compact the backfilled soil to the density of the surrounding soil. Install a 6 in [150 mm] deep check slot on ditches with grades exceeding 6 percent transverse to the ditch centerline every 25 ft [7.5 m], and secure the mat in the check slots with fasteners.
228.06 Erosion Control Mat
3.Slopes Observe the planting seasons indicated. Apply the sprig, or seed indicated to the slopes before installing the permanent mat. Dig an upper anchor slot at least 12 in [300 mm] vertically into the soil at the t op end and a lower anchor slot at least 6 in [150 mm] at the bottom end, each transverse to the mat row. Secure the mat in the anchor slots with fasteners, backfill the anchor slots with soil, and compact the backfilled soil to the density of the surround ing soil. Install the erosion control mat as directed by the Resident Engineer if a concrete lined ditch intersects the slope. Overlap the mat on the concrete lined ditch at least 6 in [150 mm] and fasten adjacent to the concrete edge Install the mat so t hat the longitudinal edge will overlap the previously installed mat edge at least 3 in [75 mm]. Dig a transverse check slot at least 6 in [150 mm] deep for every 35 ft [11 m] of installed mat for slopes over 50 ft [15 m] long. Secure the mat in the check s lots with fasteners.
4.End of Roll Overlap the ends of the mat roll 3 ft [0.9 m], with the up -slope end on top.
B.Fastening the Mat Press fasteners firmly against the mat and drive them securely into the underlying soil to hold the mat in place. Instal l fasteners every 3 ft [0.9 m] along each longitudinal edge lap joint and down the center of each mat width. Offset the center fasteners 18 in [450 mm] longitudinally from the edge fasteners. Install fasteners across the width of mat at anchor slots, che ck slots, and end overlaps on 18 in [450 mm] centers.
C.Maintenance Maintain the seeded and matted areas until project completion, including reseeding, replacing mat, and refilling eroded areas.
228.05 Method of Measuremen T
The Resident Engineer will meas ure the area covered by the erosion control mat installed in place, not including overlaps between adjacent pieces of mat.
228.06 Basis of Payment
The Department will pay for each pay item at the contract unit price per the specified pay unit as follows: Pay Item: Pay Unit: EROSION CONTROL MAT Square Yard [Square Meter] Include the cost of mat fasteners and seeding in the contract unit price for Erosion Control Mat . DITCH LINER PROTECTION 229.05 SECTION 229 DITCH LINER PROTECTION
229.01 Description
This work consists of providing and installing excelsior mat or solid slab sod to protect ditch liners.
229.02 Materials
Provide materials in accordance with the following subsections: Material: Subsection: Excelsior Mat 735.04. B Solid Slab Sod 735.01 Mat Fasteners 735.05.B
229.03 Equipment — Vacant
229.04 Construction Methods
A.Placing Excelsior Mat Place the excelsior mat so that the fibers are in contact with the soil and the netting is on top of the mat. Place one strip of mat adjacent and parallel to each side of the ditch liner. Hold the mat in place with fasteners as indicated. Press them firmly against the mat and drive them into the underlying soil to secure the mat.
B.Placing Solid Slab Sod Place the type of sod as i ndicated in accordance with Subsection 230.04.A, "Solid Slab Sodding Operations." Apply 185 gal [700 L] of water and 5 lb [2.25 kg] of 10 -20-10 fertilizer per 100 ft [30 m] of ditch liner.
C.Repairs Replace damaged ditch liner protection. Restore eroded soil beneath or surrounding the ditch liner and re -grade before replacing ditch liner protection.
229.05 Method of Measuremen T
The Resident Engineer will measure Ditch Liner Protection along the centerline of the dit ch. (The linear measurement includes the ditch liner protection for both sides of the ditch to the width indicated.)
Source: Oklahoma Standard Specifications for Highway Construction, 2019 Edition. Pages 165–166 of 935.