This course provides advanced technicians, designers, and engineers with a valuable method for understanding how the aggregate structure of an asphalt mixture affects volumetrics, field compactibility, and segregation potential. The course is taught by Bill Pine, Quality Control Director of Asphalt Technology at Heritage Construction & Materials, Inc. Bill begins with the basics of the Bailey Method and then quickly builds to give students an intensive look into the Bailey Method’s full potential. Bill, who is the renowned national expert in the use of the Bailey Method, will show students the factors that influence the way aggregate particles pack together and how to define and evaluate mix types according to Bailey Method principles. Students will also learn how to incorporate and handle RAP and/or RAS into the process. Students will receive a full version of Bill’s latest edition of the Bailey Method analysis software and hands-on training by Bill on the use of this software. The instructors will go through many examples and offer plenty of question/discussion time to maximize student comprehension.
More Information on Utilizing the Bailey Method
The Bailey method was originally developed by Robert D. Bailey of the Illinois Department of Transportation in the early 1980s. It is a practical tool that has been successfully utilized for developing and analyzing hot asphalt mixes in the lab and field. The Bailey method provides a good starting point for mix design and an invaluable aid when making adjustments at the plant to improve air voids, VMA and the overall workability of the mix, whether you are using Marshall or Superpave. The paper describes the methodology in detail with some real life examples to help mix designers and contractors better understand the mixes that are currently being used across Canada.
Essentially, the “Bailey Method of Gradation Selection” is a tool for developing and analyzing blend gradations in the lab and field. It gives designers and contractors a better appreciation of aggregate packing and its influence on mix volumetrics and compactibility. The method includes guidelines for evaluating aggregates and the aggregate blend by volume, as well as by weight, and makes provision for the use of Reclaimed Asphalt Pavement (RAP).
The focus of the Bailey method is aggregate packing. In order to better understand aggregate packing, we need to determine what particles form the coarse aggregate structure and which ones fit into the voids created within that structure.
The Bailey Method applies to coarse-graded, fine-graded and SMA mixtures. The method can help explain why some Superpave mixes are difficult to compact. It also provides insight as to why small gradation changes, which often occur during production and are within allowable tolerances, can cause significant changes to mixture volumetric properties and/or field compactibility.
- Bailey Method Achieving Volumetrics and HMA Compactibility Paper
- Bailey Method Powerpoint
- Bailey Method Bailey Method Offers Technicians Volumetric Control From AsphaltPro Magazine Jan 2009
Note: A laptop is necessary for this course! Students should bring a laptop computer pre-loaded with a fully operational copy of Microsoft Word and Excel 2010® or newer and Adobe Reader®. Students will not be downloading any software, simply receiving a USB device which holds the Word, Excel (with macros) and PDF files to be used during and after the course.