Reinforced concrete, also called ferroconcrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is usually, though not necessarily, steel bars (rebar) and is usually embedded passively in the concrete before the concrete sets. However, post-tensioning is also employed as a technique to reinforce the concrete. In terms of volume used annually, it is one of the most common engineering materials. In corrosion engineering terms, when designed correctly, the alkalinity of the concrete protects the steel rebar from corrosion.
Rebar, known when massed as reinforcing steel or reinforcement steel, is a steel bar used as a tension device in reinforced concrete and reinforced masonry structures to strengthen and aid the concrete under tension. Concrete is strong under compression, but has low tensile strength. Rebar significantly increases the tensile strength of the structure. Rebar's surface features a continuous series of ribs, lugs or indentations to promote a better bond with the concrete and reduce the risk of slippage.
Limit State Design (LSD), also known as Load And Resistance Factor Design (LRFD), refers to a design method used in structural engineering. A limit state is a condition of a structure beyond which it no longer fulfills the relevant design criteria. The condition may refer to a degree of loading or other actions on the structure, while the criteria refer to structural integrity, fitness for use, durability or other design requirements. A structure designed by LSD is proportioned to sustain all actions likely to occur during its design life, and to remain fit for use, with an appropriate level of reliability for each limit state. Building codes based on LSD implicitly define the appropriate levels of reliability by their prescriptions.
Prestressed concrete is a form of concrete used in construction. It is substantially "prestressed" (compressed) during production, in a manner that strengthens it against tensile forces which will exist when in service.
A concrete block, also known as a cinder block in North American English, breeze block in British English, concrete masonry unit (CMU), or by various other terms, is a standard-size rectangular block used in building construction. The use of blockwork allows structures to be built in the traditional masonry style with layers of staggered blocks.
Silica fume, also known as microsilica, is an amorphous (non-crystalline) polymorph of silicon dioxide, silica. It is an ultrafine powder collected as a by-product of the silicon and ferrosilicon alloy production and consists of spherical particles with an average particle diameter of 150 nm. The main field of application is as pozzolanic material for high performance concrete.
Nathan Mortimore Newmark was an American structural engineer and academic, who is widely considered one of the founding fathers of earthquake engineering. He was awarded the National Medal of Science for engineering.
Fireproofing is rendering something resistant to fire, or incombustible; or material for use in making anything fire-proof. It is a passive fire protection measure. "Fireproof" or "fireproofing" can be used as a noun, verb or adjective; it may be hyphenated ("fire-proof").
Anchor bolts are used to connect structural and non-structural elements to concrete. The connection can be made by a variety of different components: anchor bolts, steel plates, or stiffeners. Anchor bolts transfer different types of load: tension forces and shear forces.
Fiber-reinforced concrete or fibre-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity. It contains short discrete fibers that are uniformly distributed and randomly oriented. Fibers include steel fibers, glass fibers, synthetic fibers and natural fibers – each of which lend varying properties to the concrete. In addition, the character of fiber-reinforced concrete changes with varying concretes, fiber materials, geometries, distribution, orientation, and densities.
Dr. W. Gene Corley, P.E. was an American structural engineer and "preeminent expert on building collapse investigations and building codes." Corley was the Senior Vice President of CTLGroup from 1987 to 2013, where he led structural engineering projects, including numerous evaluations of buildings and structures damaged by earthquake, explosions, and from terrorist attacks. He led the investigation of structural performance of the Murrah Building following the Oklahoma City bombing in 1995, and the World Trade Center Building Performance Study in 2001–2002 following the September 11, 2001 attacks. He died on March 1, 2013. He was 77.
Zdeněk Pavel Bažant is McCormick School Professor and Walter P. Murphy Professor of Civil Engineering and Materials Science in the Department of Civil and Environmental Engineering at Northwestern University's Robert R. McCormick School of Engineering and Applied Science.
Jack Raymond Janney, born in Alamosa, Colorado, was a U.S. structural engineer and an innovator in the understanding of structural behavior and a recognized leader in the investigation of structural collapses. Janney's love of mathematics and science spurred his decision to become an engineer, and in 1942, he enrolled in the College of Engineering at the University of Colorado at Boulder. After only one semester, Janney left college and enlisted in the Navy where he became a decorated pilot during World War II.
Abraham Burton Cohen was an American civil engineer notable for his role in designing innovative and record-breaking concrete bridges such as the Delaware, Lackawanna and Western Railroad's Tunkhannock Viaduct, the world's largest concrete structure when completed. Cohen was an active member of the American Concrete Institute and earned ACI's Wason Medal for Most Meritorious Paper in 1927.
Concrete has relatively high compressive strength, but significantly lower tensile strength. The compressive strength is typically controlled with the ratio of water to cement when forming the concrete, and tensile strength is increased by additives, typically steel, to create reinforced concrete. In other words we can say concrete is made up of sand, ballast, cement and water.
A reinforced concrete column is a structural member designed to carry compressive loads, composed of concrete with an embedded steel frame to provide reinforcement. For design purposes, the columns are separated into two categories: short columns and slender columns.
Reinforced concrete is concrete in which reinforcement bars ("rebars"), reinforcement grids, plates or fibers are embedded to create bond and thus to strengthen the concrete in tension. The composite material was invented by French gardener Joseph Monier in 1849 and patented in 1867.
Ashraf Habibullah is a Pakistani-American structural engineer and software developer best known as the founder, president, and CEO of Computers and Structures, Inc., a structural and earthquake engineering software company based in Berkeley, California. Upon founding the privately held company in 1975, Ashraf co-created the first structural-engineering software available to the personal computer, and has since created a suite of products, and developed their capabilities. Notably, ETABS, a multi-story building analysis and design software, received recognition as one of the Applied Technology Council and Engineering News-Record Top Seismic Products of the 20th Century. Today, CSI is recognized globally as the pioneer in the development of software for structural and earthquake engineering. CSI's software is used by thousands of engineering firms and is the choice of sophisticated design professionals in over 160 countries. Ashraf has a deep personal interest in the study of human psychology and human behavior and how they can be leveraged to help people from all walks of life reach their maximum potential.
Portland Cement Association is a non-profit organization that promotes the use of cement and concrete. The organization conducts and sponsors research, participates in setting cement manufacturing standards, and disseminates free designs of concrete-based architectural structures, among other functions.
Treval Clifford Powers (1900-1977) was a 20th-century materials scientist considered "the father of the modern science of cement-based materials." He made contributions to the understanding of the structure of fresh and hardened cement paste and achieved fundamental results on concrete rheology, workability, consistency, durability, shrinkage and swelling, creep, and resistance of concrete to frost, sulfates and abrasion. He was the father of systems theory pioneer William T. Powers.
