Duff Abrams
Encyclopedia
Duff A. Abrams was an American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 researcher in the field of composition and properties of concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

. He developed the basic methods for testing concrete characteristics still in use today. A professor
Professor
A professor is a scholarly teacher; the precise meaning of the term varies by country. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of high rank...

 with the Lewis Institute, he studied the component materials of concrete in the early 20th century.

D. A. Abrams was researcher
Researcher
A researcher is somebody who performs research, the search for knowledge or in general any systematic investigation to establish facts. Researchers can work in academic, industrial, government, or private institutions.-Examples of research institutions:...

, professor
Professor
A professor is a scholarly teacher; the precise meaning of the term varies by country. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of high rank...

, and director of the research laboratory of the Portland Cement Association in Chicago
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

. He investigated the influence of the composition of concrete mixes on the strength of the end product.

Some of the results of his research was:
  • the definition of the concept of fineness modulus
    Fineness modulus
    Fineness modulus is defined as an empirical figure obtained by adding the total percentage of the sample of an aggregate retained on each of a specified series of sieves, and dividing the sum by 100. The sieve sizes are 150μ, 300μ, 600μ, 1.18 mm, 2.36 mm, 4.75 mm, 9.5 mm,...

    ;
  • the definition of the water-cement ratio
    Water-cement ratio
    The water–cement ratio is the ratio of the weight of water to the weight of cement used in a concrete mix and has an important influence on the quality of concrete produced. A lower water-cement ratio leads to higher strength and durability, but may make the mix more difficult to place...

    ;
  • a test method for the workability of a concrete mix by using what is called Abrams cone, see concrete slump test
    Concrete slump test
    The concrete slump test is used for the measurement of a property of fresh concrete.The test is an emprical test that measures the workability of fresh concrete. More specifically, it measures the consistency of the concrete in that specific batch. It is also used to determine consistency between...

    .


In a comprehensive research program, Abrams established the relationship between the water-cement ratio and the compressive strength
Compressive strength
Compressive strength is the capacity of a material or structure to withstand axially directed pushing forces. When the limit of compressive strength is reached, materials are crushed. Concrete can be made to have high compressive strength, e.g...

 of concrete. The results were first published in 1918 in D. A. Abrams, Design of Concrete Mixtures, Bulletin 1, Structural Materials Research Laboratory, Lewis Institute, Chicago, 1918.

He was also president of the American Concrete Association (ACI) from 1930 until 1931.

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