Steel Building Frame Structure

Types of Steel Building Frames
A. Rigid Frame (Portal Frame)

• Structure: Columns + rafters connected by rigid joints.
• Span: 20–60m (clear span).
• Best for: Warehouses, factories, aircraft hangars.

B. Braced Frame

• Structure: Vertical columns + diagonal bracing (X, K, or V-bracing).
• Span: 10–30m (requires internal bracing).
• Best for: High-rise buildings, seismic zones.

C. Modular Frame

• Structure: Prefabricated steel modules assembled on-site.
• Span: Depends on module size.
• Best for: Schools, hospitals, fast-build projects.

D. Truss Frame

• Structure: Triangular trusses for long-span roofs.
• Span: 30–100m+.
• Best for: Stadiums, airports, large event halls.

E. Cable-Supported Frame

• Structure: Steel cables + masts for tension support.
• Span: 50–200m+.
• Best for: Bridges, tensile structures, iconic roofs.

Key Components of a Steel Frame Structure

Component	Function	Common Materials
Primary Frame	Main load-bearing structure (columns, beams)	Universal beams (UB), I-sections
Secondary Frame	Supports cladding (purlins, girts)	C/Z-sections (galvanized steel)
Connections	Joins beams, columns, and bracing	Bolted, welded, or moment-resisting
Bracing	Provides lateral stability	Angle bars, hollow sections
Base Plates	Anchors columns to foundation	Thick steel plates + anchor bolts
Cladding	Roof/wall covering	Metal sheets, sandwich panels

 Advantages of Steel Frame Structures

High Strength-to-Weight Ratio – Stronger than concrete or wood.
Fast Construction – Prefabricated components reduce build time.
Design Flexibility – Adaptable for arches, curves, and cantilevers.
Durability – Resists fire, termites, and corrosion (if properly coated).
Sustainability – Recyclable and reduces construction waste.

Common Applications

Industrial – Factories, warehouses, power plants.
Commercial – Offices, malls, airports.
Residential – High-rises, prefab homes.
Specialized – Stadiums, bridges, transmission towers.