ABSTRACT
Concrete has gained so much importance and popularity because of the development of reinforced concrete. Introducing the reinforcing bars in concrete makes the concrete an excellent composite building material which can resist significant amount of tensile stresses/strains also. Steel bars embedded in the tension zone of concrete make it able to resist tension. There are three design philosophies for the design of reinforced concrete and prestressed concrete: working stress method, ultimate load method and limit state method. Analysis of a given reinforced concrete section at the ultimate limit state of flexure implies the determination of the ultimate moment of resistance of the section. Concrete has a very good compressive strength and almost negligible tensile strength. Hence, steel reinforcement is used on the tensile side of concrete. The doubly reinforced beams have two types of problems: design type and analysis type.
