The average person thinks that concrete has been in common use for many centuries, but such is not the case. Although the Romans made cement – called Pozzolana – before Christ by mixing slaked lime with a volcanic ash from Mount Vesuvius and used it to make concrete for building, the art was lost during the Dark Ages 5th century -15th century A.D.) and was not revived until eighteenth and nineteenth centuries. Marcus Vitruvius Pollio, an Architect/Engineer during the golden age of Caesar Augustus (around 25 BC). In his textbook, quite humbly titled On the Origin of all Things, Vitruvius held forth on the fundamental behavior of building materials, and then presented his views about the nature of theory versus practice, Vitruvius suggestion that design engineers should have more construction experience, and vice versa.
In the mid-1800s, Joseph Lambot, constructed a small boat and received a patent in 1855. Another Frenchman, Francois Coignet, published a book in 1861, describing many applications and uses of reinforced concrete.
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| House of Francois Coignet, built in 1853 |
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| M F. Coignet System 1855 to 1860 |
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| Reinforced Concrete Beam - Monier System -1867 |
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| Reinforced Concrete - Monier System -1867 |
Joseph Monier, the owner of an important nursery in Paris, generally deserves the credit for making the practical use of reinforced concrete in 1867. He acquired first French patent in 1867 for iron reinforced concrete tubs, followed by his pipes, tanks in 1868, flat plates in 1869, bridges in 1873, stairways in 1875. He APPARENTLY NO QUANTITATIVE KNOWLEDGE regarding it's behavior or any methods in making design calculations. In the United States, the pioneering were made by Thaddeus Hyatt, Hyatt experiments were unknown until 1877, when he published his works privately. Ernest L. Ransome was the first to use and patent in 1884, the deformed (twisted) bars. In 1890, Ransome built the Leland Stanford Junior Museum in San Francisco, a reinforced concrete building a two stories in height and 312ft (95m) long. Since that time, development of reinforced concrete in the United States has been rapid.
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| Reinforced Concrete - E. L. Ransome System -1889 |
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| Reinforcement Arrangement -Ransome System -1889 |
During 1891-1894, various investigators in Europe published theories and test results; among them were Moeller (Germany), R. Wusch (Hungary), J. Melan (Austria), F. Hannebique, 1842-1921 (France), and F. von Emperger (Hungary), but practical use was less extensive than in United States. Throughout the entire period 1850 -1900, relatively little was published, as the engineers working in the reinforced concrete field considered construction and computational methods as trade secrets.
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| Bridge at Menier, built by Armand Considere, 1906 -Photo Jacques Mossot |
One of the first publications that might be classified as a textbook was that of Considere in 1899. In 1903, with the formation in the United States of a joint committee of representatives of all organizations interested in reinforced concrete, uniform applications of knowledge to design were initiated.
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| First Reinforced Concrete Skyscraper by E. L. Ransome 1903 |
The earliest textbook in English was that of Frederick E. Turneaure and Maurer published in 1907 entitled “Principles of Reinforced Concrete Construction”. In the first decade of the twentieth century, progress in reinforced concrete was rapid. Extensive testing to determine beam behavior, compressive strength of concrete, and modulus of elasticity was conducted by Arthur N. Talbot at the University of Illinois, by Frederick E. Turneaure and Morton O. Withey at the University of Wisconsin, and by Bach in Germany, among others.
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| First reinforced concrete text by F. E. Turneaure |
In 1906 major or disastrous earthquake struck San Francisco, California (magnitude was 7.9), hence engineers conducted research extensively and revised and improved methods of design.
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| San Francisco Earthquake 1906, Magnitude 7.9 |
From about 1916 to the mid - 1930s, research centered on axially loaded column behavior. In the late 1930s and 1940s, eccentrically loaded columns, footings, and the Ultimate Strength of beams received special attention.
With the interest in and understanding of the elastic methods of analysis in the early 1900s, the elastic Working Stress method (also called Allowable-Stress Design or straight-line design) was adopted almost universally by codes as the best for design. The first modification of the elastic Working Stress method resulted from the study of axially loaded columns in the early 1930s. By 1940s, the design of axially loaded columns was based on Ultimate Strength.
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| Stress block by Charles S. whitney |
In the 1930s, Charles S. Whitney an american civil engineer proposed the use of a rectangular compressive stress distribution to replace that an average stress of 0.85f’c is used with a rectangle of depth a = β1 x, determine so that a/2 = k 2 x. In 1942 Charles S. Whitney presented a paper emphasizing this fact and showing how a probable stress-strain curve with reasonable accuracy, a parabola be replaced with an artificial rectangular stress block.
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| Depth of Rectangular stress block and c distance |
With the rectangular stress block simplification, the 1956 ACI-318 code added an appendix permitting Ultimate Strength Design (USD) as an alternate to Working Stress Design (WSD). The 1963 ACI-318 Code gave both methods equal standing.
Since the mid-1950s, reinforced concrete design practice has made the transition from that based on elastic methods to the one based on strength.
References:
- NSCP Code, Volume 1 - Buildings and other vertical Structures, 5th edition -2001 and 2010 edition;
- NSCP Code, Volume 2 - Bridges, 2nd edition -1997;
- Building Code Requirements for Structural Concrete, ACI 318-2002 and 2005, American Concrete Institute;
- Reinforced Concrete Design Volume 2, by Venancio I. Besavilla, Jr.-1998;
