Ten Potential Cement-Related Causes": this illustrated ebook is a checklist of some of the main causes of cement-related low strength in concrete or mortar. Cement glossary: glossary of over cement-related definitions and chemical formulae. If you are not already a subscriber, just sign up using the box below and you can be downloading the ebook, glossary and photos within a minute or two.
Make sure you bookmark the resources page so you can get back to it later - there are no links to it from the website navigation as it is for Cembytes subscribers only!
If you are already a subscriber to Cembytes, you can access the Cembytes Resources Page directly if you have bookmarked it. However, if you have forgotten how to reach the Resources page, you can easily get back to it. Just enter your email in the signup box below and if you are on the subscriber list you will see a link to the Resources Page. Note: we currently have two Cembytes subscriber lists, and old one and a new one, and we are gradually transferring to the new one.
Depending when you subscribed, you will be on one list or the other. If you are on the old list, the signup box won't recognize you because it is only connected to the new list, but that's fine. Just confirm your subscription and you will be on the new list. After you confirm you will receive an email with a link to the Resources Page. Articles like this one can provide a lot of useful material.
However, reading an article or two is not really the best way to get a clear picture of a complex material like cement. To get a more complete and integrated understanding of cement and concrete, do have a look at the Understanding Cement book or ebook.
This easy-to-read and concise book contains much more detail on concrete chemistry and deleterious processes in concrete compared with the website.
For example, it has about two-and-a-half times as much on ASR, one-and-a-half times as much on sulfate attack and nearly three times as much on carbonation. It has sections on alkali-carbonate reaction, frost freeze-thaw damage, steel corrosion, leaching and efflorescence on masonry.
It also has about four-and-a-half times as much on cement hydration comparisons based on word count. Click here for more information. Check the Article Directory for more articles on this or related topics. In , Thomas Edison received a patent for the first long kiln. This was about 70 feet longer than the kilns in use at the time.
Industrial kilns today may be as long as feet. Although there were exceptions, during the 19 th century, concrete was used mainly for industrial buildings. It was considered socially unacceptable as a building material for aesthetic reasons.
The first widespread use of Portland cement in home construction was in England and France between and by Frenchman Francois Coignet, who added steel rods to prevent the exterior walls from spreading, and later used them as flexural elements. Wilkinson in In , American mechanical engineer William Ward completed the first reinforced concrete home in the U.
It still stands in Port Chester, New York. Ward was diligent in maintaining construction records, so a great deal is known about this home. In , George Bartholomew poured the first concrete street in the U. The concrete used for this street tested at about 8, psi, which is about twice the strength of modern concrete used in residential construction. Court Street in Bellefontaine, Ohio, which is the oldest concrete street in the U.
Although in cement manufacturers were using more than 90 different formulas, by , basic testing -- if not manufacturing methods -- had become standardized. During the late 19 th century, the use of steel-reinforced concrete was being developed more or less simultaneously by a German, G.
Ransome started building with steel-reinforced concrete in and patented a system that used twisted square rods to improve the bond between steel and concrete. Most of the structures he built were industrial. Hennebique started building steel-reinforced homes in France in the late s.
He received patents in France and Belgium for his system and was highly successful, eventually building an empire by selling franchises in large cities. He promoted his method by lecturing at conferences and developing his own company standards.
As did Ransome, most of the structures Hennebique built were industrial. In , Wayss bought the rights to a system patented by a Frenchman named Monier, who started out using steel to reinforce concrete flower pots and planting containers. Wayss promoted the Wayss-Monier system.
In , August Perret designed and built an apartment building in Paris using steel-reinforced concrete for the columns, beams and floor slabs. The building was widely admired and concrete became more widely used as an architectural material as well as a building material.
Its design was influential in the design of reinforced-concrete buildings in the years that followed. In , the first concrete high-rise building was constructed in Cincinnati, Ohio. It stands 16 stories or feet tall. In , the first load of ready-mix was delivered in Baltimore, Maryland. The building had an automobile test track on the roof. In , he built two gigantic parabolic-arched airship hangars at Orly Airport in Paris.
In , he was granted a patent for pre-stressed concrete. Air entrainment was an important development in improving the durability of modern concrete.
Air entrainment is the use of agents that, when added to concrete during mixing, create many air bubbles that are extremely small and closely spaced, and most of them remain in the hardened concrete. Concrete hardens through a chemical process called hydration. For hydration to take place, concrete must have a minimum water-to-cement ratio of 25 parts of water to parts of cement.
Water in excess of this ratio is surplus water and helps make the concrete more workable for placing and finishing operations. As concrete dries and hardens, surplus water will evaporate, leaving the concrete surface porous. Water from the surrounding environment, such as rain and snowmelt, can enter these pores.
Freezing weather can turn this water to ice. As that happens, the water expands, creating small cracks in the concrete that will grow larger as the process is repeated, eventually resulting in surface flaking and deterioration called spalling.
When concrete has been air-entrained, these tiny bubbles can compress slightly, absorbing some of the stress created by expansion as water turns to ice. Entrained air also improves workability because the bubbles act as a lubricant between aggregate and particles in the concrete. Entrapped air is composed of larger bubbles trapped in the concrete and is not considered beneficial.
Expertise in building with reinforced concrete eventually allowed the development of a new way of building with concrete; the thin-shell technique involves building structures, such as roofs, with a relatively thin shell of concrete. Domes, arches and compound curves are typically built with this method, since they are naturally strong shapes.
Steel cables were used to form a tension ring. Probably the most accomplished person when it came to building using concrete shell techniques was Felix Candela, a Spanish mathematician-engineer-architect who practiced mostly in Mexico City.
His trademark form was the hyperbolic paraboloid. Some of the most striking roofs anywhere have been built using thin-shell technology, as depicted below.
In , the Hoover Dam was completed after pouring approximately 3,, yards of concrete, with an additional 1,, yards used in the power plant and other dam-related structures. Bear in mind that this was less than 20 years after a standard formula for cement was established. Columns of blocks being filled with concrete at the Hoover Dam in February Engineers for the Bureau of Reclamation calculated that if the concrete was placed in a single, monolithic pour, the dam would take years to cool, and stresses from the heat produced and the contraction that takes place as concrete cures would cause the structure to crack and crumble.
The solution was to pour the dam in a series of blocks that formed columns, with some blocks as large as 50 feet square and 5 feet high. The Ingalls Building, as it is called, has sixteen stories, making it one of the great engineering feats of its time. These homes still exist today. Edison envisioned that his design would meet great success, and that before no time everyone in America would be living in a concrete home.
However, his vision did not become a reality as soon as he expected; in fact, concrete homes are just starting to gain popularity now, one hundred years later. Read about the benefits of concrete homes in Building a Home with Concrete.
The first load of ready mix was delivered in Baltimore, Maryland in The idea that concrete could be mixed at a central plant, then delivered by truck to the job site for placement, revolutionized the concrete industry.
Lynn Mason Scofield founded L. Scofield, the first company to produce color for concrete. Their products included color hardeners, colorwax, integral color, sealers, and chemical stains. Colored concrete has done nothing but grow in popularity since.
Read more about modern colored concrete in Coloring Concrete. In , air entraining agents were used for the first time in concrete to resist against damage from freezing and thawing. Up to this time, the dam was the largest scale concrete project ever completed. John Crossfield was the first to receive a patent for a concrete overlay.
He add latex to portland cement, aggregate, and other materials to make a covering for ship decks. Today, concrete overlays are made by blending polymer resins with cement, and widely used for their decorative appeal. Brad Bowman developed the Bomanite process, the original cast-in-place, colored, textured and imprinted architectural concrete paving, in the middle 's in Monterey, California.
The fifty years since Bowman's development have seen huge growths in the popularity of decorative concrete , changing it from plain and boring to a beautiful decorative element that can enhance the decor of any home or office.
The first concrete domed sports arena, known as the Assembly Hall, was built at the University of Illinois in
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