AC Plant Inspector may use the scale to verify batch weights or check aggregate and
The accuracy of
checked at least once a year. load cell (display drifting), a place, scale pit is full of components, or indicator not suspects the vehicle scale Coordinator for assistance.
Some scale problems you may run into, could include a bad bad scale indicator, scale undersupports damaged or out of water, sediment accumulation under any of the scale zeroed before pulling truck on scale. If the Plant Inspector is in error contact the District Weights and Measures
A weighing device that generates load slips based on the weight of material deposited into a haul vehicle. When this type of system is in use, the Weighmaster does not indicate vehicle “gross weights” or “tare weights”. Some of the load-out systems the Plant Inspector will see include batch plants with “type approved” software, capturing all batch ingredients and based on the capacity of the haul vehicle, will load the truck with the required number of batches and generate the weigh ticket. Silos that use multiple load cells and a “type approved” computerized software system can generate weight tickets. The system captures the beginning weight of material in the silo, then material is automatically or manually placed in the truck, and the system captures an ending weight of material remaining in the silo. The Plant Inspector may use a vehicle scale to verify weights generated by these types of load-out systems.
Communication An open line of communication with all the team members is of the utmost importance. The Resident Engineer will want to know if a change in bin percentages is needed, if a change in the asphalt content is being contemplated, if aggregate grading results vary, or any variability with the plant operations is observed. The Materials Laboratory will be able to discuss any changes to test maximum density (TMD), stabilities, or voids, which would indicate changes to the AC mixture. The Street Inspector is a good resource for windrow and mat temperatures, mix segregation and where it is occurring (i.e., truck, windrow or mat) as well as any issues with trucking. The Street Sampler/tester will have information about the relative compaction. Problems with relative compaction could indicate changes to aggregate proportions or asphalt content. The Plant Operator is a wealth of knowledge for the Plant Inspector, and vice-a-versa. Keeping an open line of communication at this level is invaluable.
Every AC plant, whether batch or continuous mix must have a current CT 109 certification as well as a safety inspection. Batch Plants must have the CT 109 performed one per year while continuous mix plants must have a CT 109 performed one every six month. A new CT 109 must be performed again if either type of plant has been moved or if repairs have affected any proportioning device or scale.