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II . 1"'"1 ..., compatible admixtures. Submit both mixes for approval as separate mix designs, both meeting all requirements of this Section. Ensure that the redesigned mix exhibits plastic and hardened qualities which are additionally approved by the Engineer as suitable for placement with the original mix. The Engineer will approve the redesigned mix for commingling with the original mix and for a specific project application only. Alternately, place a construction joint at the location of the change in concretes. 346-6.2.1 Material Substitutions: Aggregate sources may be substituted within an approved base mix design provided that the aggregate are the same type, the same geological formation and are from an approved source. Obtain the Department's approval for any material substitutions before beginning concrete placement. Provide a new base mix design for any cementitious material or admixture substitution. The Department may take up to five working days to review any material substitution request. For every material substitution made, perform testing for chlorides and assure compliance with 346-4.2. Ensure the substituted mix meets the theoretical yield requirements, does not exceed the maximum water to cementitious materials ratio, and the cement content equals or exceeds, the approved base mix design. The Department may require a single 3.0 yd3 [2.3 m3] minimum test batch at the approved concrete production facility to demonstrate that the plastic properties of the adjusted mix design is within the slump and air tolerances provided in Table 2. The theoretical unit weight of the proposed mix design will be within 2.0 Ibs/ft3 [35 kg/m3] of the originally approved theoretical mix design unit weight. Approved adjusted mixes may be transferred. At any time if the Engineer determines that unsatisfactory results are obtained during production, return to the originally approved base mix design or obtain approval of a new mix design 346-6.3 Delivery Certification: Ensure that an electronic delivery ticket is furnished with each batch of concrete before unloading at the placement site. Ensure that the materials and quantities incorporated into the batch of concrete is recorded on the delivery ticket. Include the following information on the Delivery Ticket: (1.) Arrival time at job site, (2.) Time that concrete mix has been completely discharged, (3.) Number of revolutions upon arrival at the job site, (4.) Total gallons [liters] of water added at the job site, (5.) Additional mixing revolutions when water is added, (6.) Total number of revolutions at mixing and agitating speed. Items 3 through 6 do not apply to non-agitating concrete transporting . r'l . .., . ,., . .., . ,., . Ii . r"1 . ,., . M . . ,..., . r-, . vehicles. .., Ensure the batcher responsible for production of the batch of concrete signs the delivery ticket, certifying the batch of concrete was produced in accordance with the Contract Documents. Sign the delivery ticket certifying that the maximum specified water to cementitious materials ratio was not exceeded due to any jobsite adjustments to the batch of concrete, and that the batch of concrete was delivered and placed in accordance with the Contract Documents. 346-6.4 Tolerances: Meet the following tolerances from target values for plastic concrete properties specified in 346-3.1 : . II . II . 1 . ..... 09/09 01000-99 03-4122.F -