This edition will have color illustrations. Concrete is an extraordinarily versatile building material used for utilitarian, ornamental, and monumental structures since ancient times. Composed of a mixture of sand, gravel, crushed stone, or other coarse material, bound together with lime or cement, concrete undergoes a chemical reaction and hardens when water is added. Inserting reinforcement adds tensile strength to structural concrete elements. The use of reinforcement contributes significantly to the range and size of building and structure types that can be constructed with concrete. This Brief provides an overview of the history of concrete and its popularization in the United States, surveys the principal causes and modes of concrete deterioration, and outlines approaches to repair and protection that are appropriate to historic concrete. In the context of this Brief, historic concrete is considered to be concrete used in construction of structures of historical, architectural, or engineering interest, whether those structures are old or relatively new. Other related products: Concrete Manual : A Manual for the Control of Concrete Construction, Part 1 is available here: https://bookstore.gpo.gov/products/sku/024-003-00141-4 Concrete Manual : a Manual for the Control of Concrete Construction, Part 2 is available here: https://bookstore.gpo.gov/products/sku/024-003-00176-7 Renovation & Historic Preservation resources collection can be found here: https://bookstore.gpo.gov/catalog/science-technology/construction-architecture/renovation-historic-preservation

Over the concluding decades of the twentieth century, the historic preservation community increasingly turned its attention to modern buildings, including bungalows from the 1930s, gas stations and diners from the 1940s, and office buildings and architectural homes from the 1950s. Conservation efforts, however, were often hampered by a lack of technical information about the products used in these structures, and to fill this gap Twentieth-Century Building Materials was developed by the U.S. Department of the Interior’s National Park Service and first published in 1995. Now, this invaluable guide is being reissued—with a new preface by the book’s original editor. With more than 250 illustrations, including a full-color photographic essay, the volume remains an indispensable reference on the history and conservation of modern building materials. Thirty-seven essays written by leading experts offer insights into the history, manufacturing processes, and uses of a wide range of materials, including glass block, aluminum, plywood, linoleum, and gypsum board. Readers will also learn about how these materials perform over time and discover valuable conservation and repair techniques. Bibliographies and sources for further research complete the volume. The book is intended for a wide range of conservation professionals including architects, engineers, conservators, and material scientists engaged in the conservation of modern buildings, as well as scholars in related disciplines.