CATEGORY 300 DRAINAGE SECTION 313 — GABIONS
313.01 Description
Protect slopes and channels by placing stone filled wire baskets.
313.02 Materials
Stone for Gabions 901.05 Wire for Gabions 906.01 Geotextile Section 919, Class as specified
313.03 Construction
313.03.01 Excavation. Excavate, including excavation for cutoff walls, to the specified lines and
grades. Ensure that the subgrade is smooth, firm, and free from protruding objects or voids that would affect the proper placement of the wire baskets or damage the geotextile. For excavated material, refer to 402.03.01.
313.03.02 Geotextile. Place geotextile on the prepared subgrade. Overlap adjacent strips at least
2 ft. Replace or repair geotextile damaged during placement of the wire baskets. 313.03.03 Wire Baskets. Begin placement with the cutoff walls. Set the empty units on the geotextile and bind the vertical ends together with wire ties or interlocking fasteners spaced to permit stretching of the units to remove kinks. Use stretching methods that do not damage the baskets. Use stakes, pins, or other approved methods to ensure proper alignment.
313.03.04 Stone. Carefully fill the basket units with stone placed by hand or machine to ensure
good alignment with a minimum of voids between stones. Avoid bulging of the mesh. Do not drop the stone from a height greater than 36 in. Place the stone to provide a minimum of two courses. Place the top layer of stone to a uniform surface. Avoid any bulging of the lid mesh. After a basket unit is filled, bend the lid over until it meets the ends of the unit. Secure the lid to the sides and ends with wire ties or interlocking fasteners. When a complete basket unit cannot be installed because of space limitations, cut the basket unit to fit as directed.
313.03.05 Backfill. Backfill any excavation voids existing along the edges of the completed
gabions and compact in an acceptable manner. 2025 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS
313.04 Measurement and Payment
and for all material, labor, equipment, tools, and incidentals necessary to complete the work. 2025 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS Gabions, including cutoff walls will be measured and paid for at the Contract unit price per cubic yard of stone filled wire baskets complete in place. The payment will be full compensation for all excavation, geotextile, stone, ties or fasteners, backfill, compaction, disposal of excess material, 314 — FLOWABLE BACKFILL CATEGORY 300 DRAINAGE SECTION 314 — FLOWABLE BACKFILL
314.01 Description
Furnish, haul, and place flowable cement stabilized backfill material. When specified, use for utility cut backfill, pipe backfill, or for filling abandoned pipes.
314.02 Materials
Controlled Low Strength Material 902.16
314.02.01 Fillers. When required, fillers shall be natural aggregates with a maximum size of
3/4 in. and may include sands. Bottom ash shall not be used as filler.
314.02.02 Components. Toxic and deleterious components shall not be used in the backfill
mixture. The mixture shall have a 28 day, unconfined compressive strength of at least 100 psi based on the manufacturer's certification. Certification shall include the actual test data for each mixture to be used.
314.02.03 Analysis. Chemical analysis of the fly ash used in the mixture shall conform to U.S.
EPA EP Toxicity Standards. Whenever the coal source is changed or replenished, and when fly ash from a different source is used, conduct an analysis of the fly ash from each stockpile. Submit the results of the analysis to the Engineer for approval prior to using the mixture.
314.03 Construction
Place the material according to the manufacturer’s recommendations or as directed by the Engineer. Backfill utility trenches full depth to the top of the subgrade. Fill all voids during the backfill operation. Protect the backfilled utility cut from freezing and traffic for 24 hours. Wait at least 24 hours after backfilling is complete and approved by the Engineer before beginning the paving operations. Fill abandoned pipes with backfill after each end of the pipe has been adequately plugged. Refer to 303.03.06. Cut two holes into the plug at the upstream end and pump backfill into the pipe through one of the holes until the pipe is filled. Keep and submit detailed records of all flowable backfill placed. Include the source of the fly ash, the date placed, the location, depth, and the quantity used. 2025 STANDARD SPECIFICATIONS FOR CONSTRUCTION AND MATERIALS