In Depth Review 2022 Section 709 329 SECTION 709
709.01 Description
This work consists of furnishing and installing geosynthetics.
709.02 Equipment
Reserved.
709.03 Materials
Item Section Geosynthetics 858
709.04 Construction Requirements
A.General. Package, label, identify, handle, and store geosynthetic according to ASTM D 4873. Wrap each geosynthetic roll (excluding Geogrid – Type G and Reinforcement Geogrid – Type RG) with a material that will protect the roll, including the ends of the rolls, from damage due to shipment, water, sunlight, and contaminants. Maintain protective wrapping during periods of shipment and storage. Store geosynthetic onsite elevated off the gr ound. Install geosynthetic only after receiving approval from the Engineer. Place the geosynthetic on a surface that is smooth and free of stones, sticks, and other debris or irregularities that could damage the geosynthetic. Manually pull the geosynthetic taut to remove wrinkles. Do not operate construction equipment directly on the geosynthetic. If sewn, place geosynthetic with all seams up. Overlap or sew the joints. Overlap as required for the specific geosynthetic type. U se Kevlar, polypropylene, or polyester thread when sewing joints . Use a 401 stitch conforming to ASTM D 6193 for all seams. Use SSn-2 overlapping “J” seams for field seams. Sew all seams with two parallel stitch lines spaced approximately 1/4 inch apart. Place the outside stitch 1 inch from the edge of the geosynthetic. Sew seams that meet the strength requirements for the specific geosynthetic type. Furnish a sewn seam sample that has the same geosynthetic material, thread, seam spacing and number, and field seam overlap distance that will be used in the work. After laydown, cover geosynthetic material within 5 days. Remove and replace material that is not covered within 5 days.
B.Geosynthetic Drainage Material (Type D). Secure geosynthetic using the manufacturer’s recommended meth ods. After securing geosynthetic material in place, deposit the aggregate using methods that will not tear, puncture, or reposition the geosynthetic. Do not drop aggregate on the geosynthetic from a height greater than 3 feet. In Depth Review 2022 Section 709 330 C. Geosynthetic Geogrid (Type G).
1.General. Unroll geogrid parallel to the centerline of the road. Do not drag the geogrid across the underlying material. Overlap geogrid a minimum of 18 inches at all splices and joints when placing on subgrade. Overlap geogrid a minimum of 12 inches at all splices and joints when placing on base. Construct overlaps at the end of a roll so the previous roll laps over the subsequent roll in the direction of the cover material placement. Mechanically tie transverse joints to maintain the minim um overlap. Place pins , staples , or small piles of aggregate to maintain the geogrid position before placement of cover material. Place geogrid in straight segments only; when placing around curves increase overlap distances or create smaller straight segments. Patch damaged areas of geogrid. Place a patch that overlaps all sides of the damaged area by 36 inches. Mechanically tie the patch to the underlying grid.
2.Cover Material Placement. Place the first lift of material over geogrid to a depth of 8 inches of loose material. Use low ground pressure equipment to spread the initial lift of material. If rutting occurs, fill the ruts with additional material before placing the subsequent lift. Blading out ruts is not an allowable method of rut removal. Do not turn construction equipment on the first layer of material.
D.Geosynthetic Reinforcement (Type R).
1.General. Unroll geosynthetic parallel to the centerline of the road. Place the geosynthetic taut and pin the geosynthetic using pins at least 6 inches in length. Place pins at all corners and at 15-foot intervals along all edges, before placing material on the geosynthetic. Overlap the geosynthetic a minimum of 18 inches at all spli ces or joints. Construct joints at the end of a roll so that the previous roll laps over the subsequent roll in the direction of the material placement. Patch damaged areas by overlapping the tear a minimum of 36 inches with geosynthetic and secure the perimeter of the patch area with pins or staples.
2.Cover Material Placement. Place an 8 inch loose initial lift of material above the geosynthetic. Use low ground pressure equipment to spread the initial lift of material. If rutting occurs, fill the ruts with additional material before placing the subsequent lift. Blading out ruts is not an allowable method of rut removal. Do not turn construction equipment on the first layer of material. In Depth Review 2022 Section 709 331 E. Geosynthetic for Riprap (Type RR). Place geosynthetic with the longest dimension parallel to the direction of water flow. Place overlaps so the upstream strip overlaps the downstream strip. Overlap splices and joi nts at least 18 inches. Overlap splices and joints placed underwater at least 36 inches. Pin or staple all overlaps at 3-foot intervals. Patch damaged areas by overlapping the tear a minimum of 36 inches with geosynthetic and secure the perimeter of the patch area with pins or staples. Material placed to protect against wave action may be unrolled parallel or perpendicular to the water’s edge. Sew all joints that are parallel to the water’s edge.
F.Geosynthetic Separation Material (Type S).
1.General. Unroll the geosynthetic in line with the placement of the new material. Do not drag the geosynthetic across the underlying material. Use geosynthetic widths that produce overlaps of parallel rolls at the centerline and at the shoulders and so that no overlaps are required along wheel paths. Overlap the geosynthetic a minimum of 18 inches at all splices or joints. Construct joints at the end of a roll so that the previous roll laps over the subsequent roll in the direction of the material placement. Patch damaged areas by overlapping the tear a minimum of 36 inches with geosynthetic and secure the perimeter of the patch area with pins or staples. Secure the geosynthetic using the manufacturer’s recommended methods.
2.Cover Material Placement. Place the initial lift of material above the geosynthetic to a depth of 8 inches of loose material. When placing the initial lift of material, limit construction equipment in size and weight so rutting in the initial lift is less than 3 inches. If rutting occurs, fill the ruts with additional material before placing the subsequent lift. Blading out ruts is not an allowable method of rut removal. Do not turn construction equipment on the first layer of material.
G.Geosynthetic Reinforcement Geogrid (Type RG).
1.General. Place the geosynthetic reinforcement in continuous longitudinal panels with the strength (roll) direction oriented perpendicular to the face of the embankment slope/retaining wall face. Do not drag the geogrid across the underly ing material. Do not splice the geosynthetic reinforcement by any method in the primary strength direction. Overlap geogrid a minimum of 12 inches at all joints. Mechanically tie transverse joints to maintain the minimum overlap. Place pins, staples, or small piles of aggregate to maintain the geogrid position before placement of cover material. Cut or increase overlaps to conform to curves. In Depth Review 2022 Section 709 332 2. Cover Material Placement. Place the first lift of material over the geosynthetic reinforcement geogrid to a depth of 8 inches of loose material. Use low ground pressure equipment to spread the initial lift of material. If rutting occurs, fill the ruts with additional materi al before placing the subsequent lift. Blading out ruts is not an allowable method of rut removal. Do not turn construction equipment on the first layer of material .
709.05 Method of Measurement
The Engineer will measure, completed and in place, as specified in Section 109.01, “Measurement of Quantities” and as follows: The Engineer will not measure overlaps, drainage trenches, or cutoffs.
709.06 Basis of Payment
Pay Item Pay Unit Geosynthetic Material Type __ Square Yard Such payment is full compensation for furnishing all materials, equipment, labor, and incidentals to complete the work as specified. Section 714 333 SECTION 714 CULVERTS, STORM DRAINS, EDGEDRAINS, AND UNDERDRAINS
714.01 Description
This work consists of installing culverts, storm drains, edgedrains, and underdrains.
714.02 Equipment
Reserved.
714.03 Materials
A.Culverts and Storm Drains. Item Section Reinforced Concrete Culvert, and Storm Drain Pipe 830.01 A Precast Reinforced Concrete Manhole Sections 830.01 B Metallic (Zinc or Aluminum) Coated Corrugated Steel Culverts, Storm Drains, and Underdrains 830.02 B Smooth Wall Steel Pipe Culverts 830.02 F Polymer Coated Corrugated Steel Pipe 830.02 C Corrugated Polyethylene Culverts 830.03 F Geosynthetic Material – Type S2 858.01 Provide mortar consisting of a mixture of one part Portland Cement to two parts mortar sand, and sufficient water to furnish proper consistency. Where placing new end sections on existing pipe, identify whether the type of end section needed is male or female. If using polymer coated corrugated steel pipe, install end sections that meet the requirements of Section 830.02 C “Polymer Coated Corrugated Steel Pipes ” or
830.02 B, “Metallic (Zinc or
Aluminum) Coated Corrugated Steel Culverts, Storm Drains, and Underdrains”.
B.Underdrains. Item Section Perforated, Corrugated Polyethylene 830.03 A.4 Table 714 -01 Underdrain Aggregate Gradation Sieve Size Percent Passing 3/8 Inch 100 No. 4 95 – 100 No. 16 45 – 80 No. 50 10 – 30 No. 100 0 – 10 No. 200 0 – 3
Source: North Dakota Standard Specifications for Road and Bridge Construction, 2022 Edition. Pages 364–367 of 550.