Asphalt Concrete Production Batch and Continuous Mix Plants
Introduction The purpose of this Plant Inspection Guide is just that “To Guide”. It is not meant to be comprehensive, it is simply an outline with general information regarding AC plants and plant inspection. This guide is geared toward an employee who may be new to this type of work or have little experience with asphalt concrete plants. We feel, with the aid of this guide and some on the job training a plant inspector will be able to perform basic AC plant inspections. It will take a considerable amount of time as an AC plant inspector before the employee will gain the experience to understand all aspects of AC plant production. If questions arise about a certain plant or a specific function of the facilities you are inspecting, the Weights and Measures Coordinator in each District Office is
always available for consultation.
So you are going to be an AC Plant Inspector?
You will be responsible for the
acceptance of all the asphalt concrete material on the job, several thousand tons, several million dollars. Many questions come to mind. What will my duties be? What should I be looking for? Are all plants the same? How is the aggregate and asphalt proportioned? How are the aggregate and asphalt mixed? Is the plant calibration current? What do I do if the material does not meet specifications?
Purpose of AC Plant Inspection To provide inspection of the facility and the materials they produce in conformance with the Caltrans Standard Specifications (Sections 6,9,26,29,39, etc.) and the Contract Special Provisions, also to insure the materials being used in the work conforms to all project requirements. Not enough emphasis can be placed on the documentation of what you observed or didn’t observe at the AC plant. You should document all conversations between yourself and the plant operator. A report or diary, stating your observations during the time of inspection, should be written on a daily basis then given to the Resident Engineer and included in the project documents.
Prior to Start of Production Prior to the start of the project, the Resident Engineer (R.E.) and you should discuss and review all the duties of the Plant Inspector. Chapter 4, Section 39 of the Caltrans Construction Manual may be used as a guide for this dicussion. The R.E. may give you complete jurisdiction, to accept or reject a portion or all of the asphalt concrete mix being made. This responsibility is normally delegated to a Plant Inspector with some prior AC plant inspection experience.
The Plant Inspector should have on hand, enough one quart asphalt sample cans to provide up to two asphalt binder samples per each day of production. A supply of