Writing the books on asphalt

A look back at Asphalt Institute publications

By Robert Horan, P.E. and Jacqueline Bartek

In certain parts of the country, people sometimes call asphalt pavement “macadam.” The term macadam is something that has been passed down through the generations from the early 20th century when asphalt pavements were often called…macadam.

The story of John McAdam (and his ideas about improving pavement performance) is just one of the interesting storylines you can find when delving into the history of the use of asphalt materials for pavements in the United States. Publications from the Asphalt Institute have a long (100-year) history of providing an authoritative resource for readers.

Communication and education

If you explore the Asphalt Institute (AI) website, you will quickly see that education is a major focus to support the mission and vision statements. This focus on education goes way back to the early days of AI. Education can take many forms, but it is widely known that one of the best ways to communicate with key components of your target audience is through publications. Since its formation a century ago, the development, promotion and wide distribution of AI publications have been a major focus. AI publications tend to be technical in nature.

In 2018 alone, Asphalt Institute sold over 3,700 publications with some of the best-selling being “MS-2 Asphalt Mix Design Methods” and “MS-22 Construction of Hot Mix Asphalt Pavements.”

Besides the large library of technical manuals, another AI publication that is highly valued is “Asphalt” magazine. The first version of the magazine was published in 1949 – making 2019 the 70th anniversary of the publication. The magazine is mailed to over 18,000 subscribers in 114 countries.

It is interesting to note that in the 1928 AI Annual Meeting minutes, there is a mention of the need to have an asphalt industry magazine. “There should be a magazine issued by and for the industry, but as yet we have not been able to secure the needed support for such an undertaking.” Today that desire is a reality. 

Early publications

Archival documents show that getting the word out about asphalt pavements in the form of publications was a major focus in the early years of AI. For instance, an excerpt from the 1922 AI Annual Meeting minutes states: “During the past year, we have distributed in the neighborhood of 100,000 publications covering practically every phase of asphalt paving work. 

These publications have won a high place in the estimation of engineers, officials and teachers and they have done much to make asphalt better known to those who have to deal with paving subjects.”

Many of the publications were created primarily to educate those directly involved with road building. In 1920, Wallace Craig, an Asphalt Institute District Engineer in the Chicago office, prepared a handbook on the proper use of asphalt which later was used as a model for the first “Asphalt Handbook.” To this day, almost 100 years later, AI still publishes that manual and it is one of their best-selling books.

In the 1929 AI minutes, it was reported that: “During this calendar year, we issued 18 new publications and five reprints of articles appearing in magazines, bringing the total number of distinct publications since the formation of the association to 200 brochures, circulars, pointers and reprints. It is worthy to comment that about 15 percent of our requests for publications came from foreign countries.”

Besides the technical publications, in the early days of the organization there was an effort to educate the general public on the use of asphalt as an important road-building material. The reason for the outreach to the general public was that the use of asphalt surfacing was relatively new in the 1920s and public acceptance was vitally important.

We noticed in each of the annual minutes, articles published in magazines and the number of clippings in newspapers were closely tracked. For instance, in the 1929 annual meeting minutes, it was reported that “…203 articles from the association were published in 3,211 newspapers for a total of 847 pages. In addition, 230 articles appeared in engineering and trade magazines covering a total of 310 pages.”

Again, a decision was made that it was critical to promote asphalt pavements to both technical and non-technical folks as a viable alternative to concrete pavement.

Training materials

Some of the most popular AI publications in the 1920s were educational brochures which included 15 primary brochures that covered a wide variety of topics related to the use of asphalt in highway and street pavements.

One of the more popular ones was entitled “Asphalt a world old material.” This document evolved and the AI archives include editions one through five. It includes a summary of the history of human’s use of asphalt that dates as far back as about 3,000 B.C. including the evolution of its use as an important highway building material all the way through “modern times.” (1925) A section on the future of asphalt featured this quote: “Experience urges the use of asphalt.

From ancient Assyria to modern America it has rendered increasing service to mankind. Its sources of supply are practically unlimited. It is stored away in enormous quantities deep within the earth and only awaits the hand of man to fashion it to his services.”

In 1932, AI began publishing specification booklets written by Prevost Hubbard. Low-cost road construction increased significantly with the continued promotion and distribution of these booklets. State highway engineers benefited from this information to learn the proper technical methods for their road construction.


Not surprisingly, the early publications contained content promoting the use of asphalt pavement as an alternative to concrete pavement. Many times, the text would include direct or indirect comparisons to concrete pavements.

Here is an example: “Its (asphalt pavement) pleasing appearance, easy-riding qualities, low tractive resistance, general freedom from cracks and rough joints, cleanliness and the fact it is easy on tires, have made it the most popular pavement in existence.”

Technology trends

The early years of AI (the 1920s) were a time of major transformations in the asphalt industry and in how asphalt pavement materials were used in construction and maintenance. Much of the efforts in the early publications were focused on explaining those changes to both the professionals involved with highways and also, in more simple terms, to the general public.

One major change was the move from the use of naturally occurring asphalt sources to the production of asphalt materials through the petroleum refining process. At the same time, AI engineers were working with other organizations toward the goal of reducing the number of asphalt grades being specified and this was accomplished in 1923 with a reduction from 102 grades to nine standard grades.

There was also an evolution in the basic types of asphalt pavement applications. One effort that was highlighted in the publications was explaining the various types of asphalt pavement applications for base/foundation mixtures and surface mixtures which are defined in Brochure #5 “Terms Used in Connection with Asphalt for Highway Work.”

The brochure listed three types of surface mixtures used for new construction and overlays which were laid on the roadway at that time. They were:

1.  Sheet asphalt – a mixture of sand and fine aggregate treated with petroleum asphalt

2.  Asphalt (penetration) Macadam – a broken-stone wearing surface layer that liquid asphalt material is poured into for the purpose of filling the voids in the pavement layer

3.  Asphalt concrete – a mixture of asphalt with broken stone, broken slag or gravel and often with sand or mineral filler as well

Continued legacy

To this day, Asphalt Institute publications are geared to not only educate those involved with pavement design, production, construction and maintenance of asphalt pavements but also the non-technical users of roadways. This philosophy is essential to ensure that asphalt pavements are viewed as a quality product that plays a vital role in the world’s infrastructure.

A great example of AI’s focus on sharing publications occurred in 2018 when the Asphalt Institute Foundation distributed 130 print books and 248 eBooks to college students studying pavement engineering. Colleges included Auburn University, California State Polytechnic (Pomona), Iowa State University and the University of Idaho.

It certainly seems that the expression “The more things change; the more things stay the same” applies to a historical look at Asphalt Institute’s publications. Whether it be in 1919 or 2019, AI has always put a premium on developing and marketing quality publications as a method in ensuring that asphalt is always recognized as the construction material of choice.

Horan is an Asphalt Institute Senior Regional Engineer based in Virginia. Bartek is the Asphalt Institute Library Services and Resource Specialist.