314 FLOWABLE BACKFILL

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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.
314.01 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. CertificationA document which verifies that the material and work complies with the applicable specifications and includes the actual test results to confirm the statement. The contents of the certification shall be on the Contractor's/vendor's/manufacturer's letterhead or approved document and shall be duly signed by a company officer. Certifications for metal products, when required, shall include a statement that the material was melted and manufactured in the United States except as provided in Section 165 of the Surface Transportation Assistance Act of 1982, as amended by Section 1041(a) and 1048(a) of the Intermodal Surface Transportation Efficiency Act of 1991 with regard to the furnishing and coating of iron and steel products. A nationwide waiver for this provision has been granted for pig iron and processed, pelletized, and reduced iron ore. 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. EPAEnvironmental Protection Agency EP Toxicity StandardsThe official Standards for Highway and Incidental Structures, maintained on the Administration website. The latest incorporated revisions issued on or before the date of advertisement of the Contract.. 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 EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. for approval prior to using the mixture.
314.03 CONSTRUCTION.
Place the material according to the manufacturer’s recommendations or as directed by the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him.. 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 EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. before beginning the paving operations.
Fill abandoned pipes with backfill after each end of the pipe has been properly 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 completely 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.
314.04 MEASUREMENT AND PAYMENT.
Flowable Backfill will be measured and paid for at the Contract unit price per cubic yard. The payment will be full compensation for all material, labor, equipment, tools, and incidentals necessary to complete the work.