Term: Reinforced concrete
**Reinforced Concrete Overview:**
– Description of reinforcing schemes to resist tensile stresses.
– Use of varied materials like steel and polymers for reinforcement.
– Importance of permanent stress for better structure behavior.
– Properties required for reinforcement: high strength, good bond to concrete, etc.
– Common methods in the US: pre-tensioning and post-tensioning.
**History and Innovations:**
– Contributions of François Coignet, Joseph Monier, Thaddeus Hyatt, Ernest L. Ransome, and G. A. Wayss in reinforced concrete.
– Evolution of iron and steel concrete construction techniques.
**Design and Behavior of Reinforced Concrete:**
– Use of reinforced concrete elements in various structures.
– Importance of designing efficient floor systems for optimal building structures.
– Understanding the behavior of reinforced concrete elements under external loads.
– Various stresses like tension, compression, bending, shear, and torsion experienced by elements.
**Materials and Mechanisms:**
– Composition of concrete and steel in reinforced concrete.
– Key characteristics like thermal expansion coefficients and protection against corrosion.
– Mechanism of composite action of reinforcement and concrete.
– Anchorage codes and anticorrosion measures for reinforced concrete.
**Innovations and Challenges in Reinforced Concrete:**
– Techniques like prestressed concrete to increase load-bearing strength.
– Common failure modes, including mechanical failure and carbonation.
– Challenges like alkali silica reaction, sulfate attack, and use of non-steel reinforcement materials.
– Advantages of plastic reinforcement like FRP and GRP in concrete applications.
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.
| Reinforced concrete | |
|---|---|
 A heavy, reinforced concrete column, seen before and after the concrete has been cast in place around its rebar frame | |
| Material type | Composite material |
| Mechanical properties | |
| Tensile strength (σt) | Stronger than concrete |