347PORTLAND CEMENT CONCRETE - CLASS NS

347-1 Description.

The requirements of this Section are applicable to concrete designated as nonstructural portland cement concrete, ( Class NS) hereinafter referred to as concrete. Use concrete composed of a mixture of portland cement, aggregates, water ; and where specified chemical admixtures, or supplementary cementitious materials. Deliver concrete to placement site in a freshly mixed, unhardened state. Ensure the concrete is placed and cured in a manner to ensure that the strength and durability of the concrete is maintained.

347-2 Materials.

347-2.1 General: Certify that all materials used in concrete are from Department

approved sources, and free from detrimental matter. Meet the following requirements: Portland Cement ................................ ......Section 921 Coarse Aggregate* ................................ ..Section 901 Fine Aggregate* ................................ ......Section 902 Water ................................ ....................... Section 923 Chemical Admixtures ............................. Section 924 Supplementary Cementitious Materials ..Section 929 * Recycled Asphalt Pavement (RAP) may replace up to 20% of the total aggregate in the design mix. Use RAP from a Department approved stockpile.

347-3 Production, Mixing and Delivery.

347-3.1 Concrete Production Requirements: Obtain concrete from a plant that i s

currently on the Department’s Nonstructural Concrete Production Facility Listing. Producers seeking inclusion on the list must contact the local District Materials Office for approval. When Volumetric Mixers are used, deliver concrete in accordance wit h the Volumetric Mixer Standards of the Volumetric Mixer Manufacture rs Bureau (VMMB ) VMMB 100-01. Substitution of structural concrete in lieu of non -structural concrete may be used if approved by the Engineer. If structural concrete is used in lieu of n on-structural concrete, obtain the concrete from a production facility meeting the requirements of Section 346. Acceptance is based on the requirements of Section 347. The Engineer may disqualify any concrete production facility for non -compliance with Specification requirements.

347-3.2 Delivery: The maximum allowable mixing, agitation, and placement time of

concrete is 120 minutes.

347-3.3 Small Quantities of Concrete: With approval of the Engineer, small quantities

of concrete, less than 3 cubic yards placed in one day and less than 0.5 cubic yards placed in a single placement may be accepted using a pre -bagged mixture.

347-4 Certification and Acceptance.

347-4.1 General: Furnish a delivery ticket with each batch of concrete before

discharging concrete at the placement site. Ensure the delivery ticket includes material quantities FY 2023-24 Return to Table of Contents incorporated into the batch, sources of material s, batch adjustments , batch size, time loaded, time discharged, and the allowable jobsite water addition . Ensure the batcher responsible for producing the concrete signs the delivery ticket, certifying that the batch was produced in accordance with the Contract Documents . Record water added at the jobsite. Sign the delivery ticket certifying that the concrete was placed in accordance with the Contract Documents . Acceptance by the Department will be by certification on the delivery ticket signed by the batcher and the Contractor . Certify that the concrete meets a minimum compressive strength of 2,500 psi at 28 days. The Engineer may verify the strength of the concrete.

347-4.2 Remedial Action: Delineate , remove to the full depth and width, and replace, at

no cost to the Department, concrete that has:

350-1 Description.

Construct Portland cement concrete pavement in one course, on a prepared subgrade or base. Use either the fixed -form or the slip -form method of construction. When reinforced cement concrete pavement is specified or required, use concrete reinforced with steel bars or welded wire reinforcement, in accordance with details shown in the Plans. The Engineer may require a demonstration of equipment and paving operations. If any uncontrolled cracks appear during the life of the Contract, remove and replace the cracked concrete at no expense to the Department. Investigate and implement immediate effective solutions to eliminate further cracks, in consultation with, and subj ect to the approval of the Engineer.

350-2 Materials.

Meet the following requirements except as modified herein: Concrete ................................ .............................. Section 346 Grinding Concrete Pavement .............................. Section 352 Curing Materials * ................................ ............... Section 925 Embedded Items ................................ .................. Section 931 Joint Seal ................................ ............................. Section 932 *Use products listed on the Department’s Approved Product List (APL). Provide concrete with a minimum 28 -day compressive strength of 3,000 psi and maximum water to cementitious materials ratio of 0.50. For concrete pavement placed using the slip -form method of construction, utilize concrete with a target slump of 1.5 inches plus or minus 1 inch . For concrete pavement placed by hand in constructed forms, utilize concrete with a target slump of 3 inches plus or minus 1.5 inches. Air content testing for concrete pavement mixes is not required .

350-3 Equipment.

350-3.1 General: Ensure the equipment and tools used have the capability of handling

materials and performing all parts of the work and meet the following requirements: To be of such capacity that the paver operates continuously and at a constant rate of production, with starting and stopping held to a minimum. When equipment operates on the side forms, use scraping devices to clean accumulatio ns from the top of the forms and wheels. The forms will be a rigid material and mortar tight. Ensure that the alignment and grade of all forms are in accordance with the contract documents, prior to the placing of concrete.

350-3.2 Slip-Form Paver: Use a self-propelled slip-form paving system consisting of a

slip-form paver and if needed, a concrete spreader to distribute , strike-off, consolidate, and screed the freshly placed concrete in one complete pass to produce a dense and homogeneous pavement requ iring minimal hand finishing. The slip -form paving machine must extrude concrete into a shape using attached molding components consisting of a profile pan and side forms. The slip -form paving machine must be equipped with the following components: FY 2023-24 Return to Table of Contents