171 SECTION 255 EROSION CONTROL BLANKET AND TURF REINFORCEMENT MAT
255.01 Description
This work consists of placing an Erosion Control Blanket (ECB) or Turf Reinforcement Mat (TRM) on a prepared slope or channel.
255.02 Equipment
Reserved.
255.03 Materials
Item Section Erosion Control Blanket and Turf Reinforcement Mat 856
255.04 Construction Requirements
A.General. Remove all rocks or clods greater than 1 inch in diameter, and all sticks and deleterious material from the area to be covered.
B.ECB and TRM Type 1. Complete seeding before placing ECB and TRM.
C.TRM Type 2. If the TRM requires soil filling, fill the TRM with topsoil, compost, or a blend of topsoil and compost. Place seed and fertilizer on the soil filled TRM. Apply hydraulic mulch or place ECB on the seeded TRM. Place the ECB with the netting on top and the fibers in contact with the soil. In ditches, unrol l the ECB and TRM starting from the top of the slope and perpendicular to contours. On embankments shorter than 10 feet, unroll the ECB horizontally or vertically to the slope.
D.Repair of ECB and TRM. Restore the damaged area to the proper contour. S eed as specified in Section 251 “Seeding” . Replace the ECB and TRM with the required type.
255.05 Method of Measurement
The Engineer will measure, completed and in place, as specified in Section 109.01 “Measurement of Quantities”. The Engineer will not measure overlaps or buried portions of the ECB or TRM. 172 255.06 BASIS OF PAYMENT Pay Item Pay Unit ECB Type 1 Square Yard ECB Type 2 Square Yard ECB Type 3 Square Yard ECB Type 4 Square Yard TRM Type 1 Square Yard TRM Type 2 Square Yard Such payment is full compensation for furnishing all materials, staples, equipment, labor, and incidentals to complete the work as specified. Section 256 173 SECTION 256 RIPRAP
256.01 Description
This work consists of furnishing or salvaging, and placing stones on slopes, channel ways, or other areas.
256.02 Equipment
Reserved.
256.03 Materials
A.General. Use stone that is clean and free of deleterious material.
B.Grout. Proportion grout using one part Portland Cement and two parts sand by volume.
C.Riprap. Use field stone or quarry stone as riprap.
1.Gradation. Table 256 -01 Riprap Gradations Grade I Grade II Grade III Size (Inches) Percent Smaller Size (Inches) Percent Smaller Size (Inches) Percent Smaller 20 100 28 100 36 100 18 70-90 22 30-80 29 55-85 15 40-60 16 20-50 24 35-50 10 0-10 10 0-5 10 10-15 6 0-2 6 0-2 6 0-2
2.Field Stone. Do not use field stone that: − Consists of sandstone, shale, or soft limestone; − Contains cracks or flaws that would cause splitting or breakup; or − Is easily abraded or crushed.
3.Quarry Stone. Do not use quarry stone that consists of sandstone, limestone, or stone of sedimentary origin. Provide quarry stone that would meet the requirements of Table 256-02, if the stone was properly processed.
Source: North Dakota Standard Specifications for Road and Bridge Construction, 2022 Edition. Pages 206–207 of 550.