9. Concrete

This chapter introduces concrete as a construction material. Currently, it is the most widely used building material in the building and construction industry. Definitions of the term according to ASTM, ISO, and EN standards are presented. Constituent materials of concrete (mainly cement, aggregates, and water) are then discussed, including the definitions and types of admixtures, which nowadays contribute to the pefroduction of cost-effective and durable concrete structures. Additions and/or supplementary cementitious materials complete the list of constituent materials. A subsequent section is devoted to properties and tests of concrete, with emphasis on workability and compression strength, the most important properties of fresh and hardened concrete, respectively. The proportion of each constituent, named concrete mix design, is then summarized. Production of concrete, i.e., handling, batching, mixing, transportation, placing, compacting, and curing, accounts for the next group of headings of the chapter. Durability of concrete is briefly described. Thus, sulfate and acid attack, alkali-aggregate reaction, frost attack—freeze-thaw damage, erosion/abrasion, fire, and corrosion are properly explained. The next section describes precast concrete elements, which are units cast and cured in a place other than the final location in the works. It includes a brief description of structural and nonstructural elements. Subsequently, reinforced concrete, which revolutionized the construction industry in the last century, is introduced. Prestressed concrete closes the chapter, taking into account the two distinct systems of prestressing, pretensioning, and post-tensioning.