Introduction to Steel Design Dr.Kamaran S.Ismail

Structural Steels

• Structural steels are considered tough because they can withstand bending, hammering, and shearing without visible damage.
• Steel's ability to be bent, hammered, and sheared without damage is due to its advantage of being ductile and having high strength.

Corrosion and Protection

• Most steels need periodic painting when exposed to air and water to prevent corrosion.
• The strength of structural members can reduce significantly in situations where corrosion occurs.

Buckling in Compression Members

• The danger of buckling in a compression member increases with an increase in length and slenderness.
• As compression members become longer and more slender, they are more susceptible to buckling.

Steel Structures and Modifications

• Steel structures can have new bays or entire wings added to them without issues due to the flexibility of steel.
• The property of ductility in steel allows it to withstand extensive deformation without failure under high tensile stresses.

Undesirable Properties of Steel

• The undesirable property of steel mentioned in the text is corrosion.

Types of Steel Structures

• Examples of structures where steel is used include high-rise buildings, long-span bridges, and industrial buildings.

Structural Shapes of Steel

• The text emphasizes the importance of structural shapes of steel, which are standardized and widely available.
• The American Institute of Steel Construction (AISC) published the Steel Construction Manual, which provides guidelines for steel design and construction.

Identification and Properties of Steel

• Structural shapes are identified for use in drawings, specifications, and designs using a standardized system.
• Steel has high strength per unit of weight, which is important in construction because it allows for efficient use of materials.
• The uniformity of steel properties is superior to reinforced-concrete structures, which can have varying properties.
• The mechanical property of steel that allows it to withstand extensive deformation without failure under high tensile stresses is ductility.

Elasticity and Permanence

• The characteristic of elasticity in steel is advantageous in design because it allows steel to return to its original shape after deformation.
• The property of permanence in steel frames implies that they can maintain their shape and structure over time.

Ductility and Structural Behavior

• The property of ductility in steel contributes to its structural behavior by allowing it to absorb energy and deform without failing under high tensile stresses.