Article 1 — Description
Furnish and incorporate all required asphalt antistripping agents in asphalt concrete paving mixtures and asphalt -stabilized base mixtures to meet moisture resistance testing requirements.
Article 2 — Materials
2.1 Lime . Provide hydrated lime or commercial lime slurry in accordance with DMS -6350 , “Lime and Lime
Slurry.”
2.2 Liquid Antistripping Agent . Provide a liquid antistripping agent that is uniform and shows no evidence of
crystallization, settling, or separation. Ensure all liquid antistripping agents arrive in: properly labeled and unopened containers, as shipped from the manufacturer ; or sealed tank trucks with an invoice to show contents and quantities. Provide product information to the Engineer , including: Safety Data Sheet, specific gravity of the agent at the manufacturer’s recommended addition temperature, manufacturer’s recommended dosage range, and handling and storage instructions.
Article 3 — Equipment
Provide all equipment to store, handle, dispense, meter, and mix asphalt antistripping agents.
Article 4 — Construction
4.1 Laboratory Design Evaluation and Production M ixture Verification . Provide a laboratory mixture design
and production mixture that meet moisture resistance requirements. Evaluate proposed asphalt pavement or base mixtures during design and production in conformance with the moisture resistance requirements in the asphalt mixture specification. Governing specifications require the Contractor or Engineer to design the mixture, and the party performing the design is responsible for the moisture susceptibility evaluation. If the Contractor designs the mixture, the Engineer verifies compliance. Determine the dosage needed to achieve the moisture resistance requirements during design if an antistripping agent is required. Use this addition rate in the production mixture. Add between 0.5% and 2.0% of hydrated lime or commercial lime slurry solids by weight of the individual aggregate treated when using lime. Add liquid antistripping agent, when used, to the binder, in conformance with the manufacturer’s instructions. Do not exceed the manufacturer’s maximum recommended dosage rate. 242 Stop production if the production mixture does not meet moisture resistance requirements and correct the problem.
4.2 Addition of Antistripping Agents at the Mix Plant . Connect the measuring device for the addition of the
asphalt antistripping agent into the automatic plant controls to automatically adjust the supply to plant production and provide a consistent percentage in the mixture. Set automatic plant controls so that an interruption of asphalt antistripping agent’s flow causes plant shutdown.
4.2.1 Lime . Incorporate lime in a manner that thoroughly and uniformly distributes lime onto the aggregate surface
or into the mixture. Use metering equipment, as approved, to ensure the required quantity of lime is used. 4.2.1.1. Hydrated Lime. Add hydrated lime to the aggregate by one of the following methods, unless otherwise shown on the plans: mix in an approved pug mill mixer with damp aggregate containing water at least 2% above saturated surface dry conditions ; or add into the drum- mix plant immediately before asphalt binder addition or in the pug mill of the weigh -batch plant before asphalt binder addition. Dry mix aggregates and lime before adding asphalt binder when a weigh batch plant is used. 4.2.1.2. Commercial Lime Slurry . Add commercial lime slurry to the aggregate by one of the following methods unless otherwise shown on the plans: mix in a suitable pug mill mixer with the aggregate; or mix with aggregate between the plant cold feeds and the dryer or mixing drum during mixture production.
4.2.2 Liqui d Antistripping Agent . Incorporate liquid antistripping agent into the binder as follows:
handle in conformance with the manufacturer’s recommendations ; add at the manufacturer’s recommended addition temperature; add into the asphalt line by means of an in-line metering device, in accordance with Item 520, “Weighing and Measuring Equipment,” and a blending device to disperse the agent; and place the metering and blending devices in an approved location.
Article 5 — Measurement and Payment
The work performed, materials furnished, equipment, labor, tools, and incidentals will not be measured or paid for directly but will be subsidiary to or included in payment quantity for other pertinent Items.