This category covers establishments primarily engaged in manufacturing concrete products, except block and brick, from a combination of cement and aggregate. Contractors engaged in concrete construction work are classified in the construction industries, and establishments primarily engaged in mixing and delivering ready-mixed concrete are classified in SIC 3273: Ready-Mixed Concrete.
327999 (All Other Miscellaneous Nonmetallic Mineral Product Manufacturing)
327332 (Concrete Pipe Manufacturing)
327390 (Other Concrete Product Manufacturing)
The products included in this industry are made of concrete, formed and hardened at the cement facility, and shipped in finished form to customers or users. Many of the items were prefabricated parts to be assembled into buildings, bridges, or parking structures. Pipe was another major segment of the industry. Other products included a variety of utilitarian and decorative items, such as burial vaults, septic tanks, monuments, and bird baths.
In contrast to products that were poured on-site, the products of this industry were made in a controlled environment, away from a construction job site. Such controlled production conditions enabled concrete products to be made more structurally sound and in accordance with construction specifications.
In 2000 the concrete products industry employed roughly 80,000 people, of which 60,000 were in production. The states with the greatest employment in the industry were California, Florida, Pennsylvania, and Texas, which accounted for 35 percent of the total industry employment.
The great majority of customers for concrete products were building contractors and construction firms. This required industry firms to deal with architects and engineers as well as management. Many of the industry's sales comprised standard or off-the-shelf items that were produced, warehoused, and sold to multiple customers. Other items were tailor-made to the specific design of particular buildings, bridges, parking structures, or other facilities. Where products made of plastic or lumber were possible alternatives, precast concrete products were sometimes preferred and selected for environmental reasons.
Companies in the industry tended to grow by acquisitions and mergers. The greater size enabled the companies to spread their marketing, research, and engineering costs over a larger number of activities. Industry firms also joined to form several trade groups, which generally conducted research into materials and methods to improve the products, performed promotion of the product specialty, and represented the industry in governmental matters. These associations included the American Concrete Institute, the American Concrete Pressure Pipe Association, the Concrete Reinforcing Steel Institute, the Post-Tensioning Institute, the Portland Cement Association, the American Segmental Bridge Institute, and the Precast/Prestressed Concrete Institute.
Industry firms continually conducted research to improve the qualities of concrete products. Areas of focus included workability, strength, durability, weight, and insulating ability. Minimum quality standards for products were established by the American Society for Testing and Materials (ASTM) and were continuously modified as technology developed and changed.
Concrete was made by mixing together cement, sand, gravel, possibly other aggregates, and water. The concrete then was molded and might be reinforced in a variety of ways to meet its different purposes. Molds were made of wood, fiberglass, concrete, or other materials. Precast concrete was poured into molds of the desired product shapes, in which it was hardened and cured. Reinforced concrete was strengthened by inserting steel rods or mixing in fibers. Prestressed concrete had steel wires or rods inserted and stretched so as to compress the concrete and make it resist tensile stresses. Other qualities of concrete were modified by use of different types of sand, gravel, crushed stone, and cement in differing proportions. All of these factors affected the properties relating to its strength, durability, workability, curing time, resistance to temperature and humidity changes, and appearance.
U.S. total cement consumption grew by 19.2 percent between 1991 and 1994; March 1995 cement prices were 5.3 percent higher than the previous year. Also, production in 1995 was reported to be reaching capacity, save in New England and California, where the industry was feeling the impact of slower economic recovery.
Construction in public works projects in the United States—infrastructure construction ranging from construction of public buildings, highways, and conduits for utilities—was predicted to increase, then level off at about $120 billion through 1998. For example, a 1992 review found many of the 600,000 bridges in the Federal Highway Administration's jurisdiction as requiring either replacement or significant repairs. The water distribution system in New York City also broke and caused frequent flood conditions in the 1980s and early 1990s. In response to increased demand, the concrete products industry was expected to continue to enhance concrete's qualities and usefulness through engineering improvements.
In 1967 there were 2,687 companies in the concrete products industry, employing 70,000 workers and shipping products valued at $5.8 billion. By 1982 there were 2,749 companies, employing 20 percent fewer employees and shipping 39 percent less product value. In the late 1990s there were approximately 2,743 establishments and roughly 80,000 employees. Total shipments for 2000 were estimated at $10.5 billion.
The concrete products industry often experienced cyclical changes along with the construction industries on which it largely depended. The industry's business fluctuations were most apparent in the total number of employees. For example, the industry stood at 58,000 workers in 1975; 66,000 in 1979; 54,200 in 1983; 70,000 in 1987; 61,000 in 1991; and 80,100 in 2000.
By far the 1999 leader in this industry sector was Oldcastle Inc. of Atlanta, Georgia. Oldcastle posted sales of nearly $2.5 billion and employed 15,000 workers. A distant second was Tarmac America Inc. of Norfolk, Virginia, with sales of $400 million and 2,300 workers. Third was Hydro Conduit Corporation of Houston, Texas, with $250 million in sales and 2,000 employees.
The concrete products industry employed 80,100 people in 2000. More than 75 percent of the industry's employees were production workers who earned an average of $13.01 per hour. The average work week was 44.5 hours with 7.5 hours of overtime. The industry's white collar jobs encompassed accounting, engineering, estimating, marketing, and management.
Industry firms conducted continuous research throughout the twentieth century to enhance the qualities of concrete products and construction operations and to improve the methods for producing and delivering concrete. Additional advancements were made by businessmen and managers, as with the adaptation of trucks for deliveries and mixing in the early part of the century.
Continual and sometimes dramatic changes in science and engineering produced positive changes in the industry. Industrialization of the precast concrete products industry began in earnest in the 1960s and 1970s as an increasing number of improvements in the strength and other qualities of concrete were made by scientific, engineering, and chemical research and analyses. Technicians in these specialties combined steel with concrete to enable its use in large bridge and skyscraper structural elements, as well as applied computers and automation to control and mix raw material ingredients accurately. Many studies and tests were conducted to determine the effects of different material ingredients, and varying proportions of those ingredients, in producing desired new concrete qualities. These scientific activities were performed by both individual companies—each hoping to improve its own competitive position—and industry-supported trade associations and institutes.
"Basically, most 'new' products in the precast concrete industry are an evolution of existing elements," according to one industry overview. "Nevertheless, the industry has developed (and is successfully marketing) valuable solutions in fields relative to, for instance, environmental problems such as sound barrier walls to protect residents living near highways or railways from noise hindrance."
In the mid-1990s there was some controversy in the United States regarding the manufacture of concrete-related products using cement made in hazardous waste burning kilns. It was thought that perhaps the toxic chemicals not destroyed in the process could leach through the pipe or other products and into the environment; however, there has been little research that would either support or refute these claims. The concern spawned legislation at the local government level banning the use of or sale of "toxic cement," including the use of concrete pipe manufactured with cement made from hazardous waste fueled kilns in public water supplies.
The use of used tires as a kiln fuel was also challenged by environmental regulations. Proponents, however, as is the case with the use of hazardous waste as a kiln fuel, argued that using spent tires was an effective form of recycling. Both practices have met with numerous legal challenges.
Bureau of Labor Statistics. Employment Statistics. Washington, D.C.: GPO, 1999. Available from http://www.bls.gov .
"Set in Concrete: Trade." The Economist, 3 June 1995.
United States Census Bureau. Economic Census 1997. Washington, D.C.: GPO, 1999. Available from http://www.census.gov .
United States Census Bureau. "Statistics for Industries and Industry Groups: 2000." Annual Survey of Manufacturers. February 2002. Available from http://www.census.gov .