Steel structures are everywhere, from warehouses and bridges to high rise towers and industrial plants. Yet their fundamental components remain unfamiliar to many. Understanding common steel profiles, their shapes, load behaviors, and connection methods is the first step toward designing safe, efficient, and cost effective buildings that stand the test of time.

H-Beams

H - Height; B - Width; t1 - Web thickness; t2 - Flange thickness; r - Corner radius;

H-beams, also called universal steel beams, are named for their cross-section resembling the letter "H". They are an economical and efficient profile with a more optimized cross-sectional area distribution and a more reasonable strength-to-weight ratio. The cross-section of an H-beam typically includes two parts: the web and the flanges, also known as the waist and the edge. H-beams are produced by both hot rolling and welding.

I-Beams

h - Height; b - Flange width; d - Web thickness; t - Average flange thickness; r - Inner arc radius;

I-beams are classified into wide, medium, and narrow flange H-beams according to the ratio of flange to web height. Wide-flange H-beams include hot-rolled ordinary H-beams, lightweight H-beams, and wide parallel-flange H-beams (H-beams). The inner wall slope of the flange is 1:6.

Channel Steel

h - height; b - flange width; d - web thickness; t - average flange thickness; | - average flange thickness; r - inner arc radius;

Channel steel is a long strip of steel with a U-shaped cross-section, divided into ordinary channel steel and light channel steel.

Specifications: For example, 100*48*5.3 indicates a channel steel with a web height of 100 mm (h), a flange width of 48 mm (b), and a web thickness of 5.3 mm (d), or called 10# channel steel.

Square Tube

B - side length; H - long side length; R - outer arc radius; t - wall thickness

Rectangular tube, also called rectangular steel pipe, is a hollow rectangular cross-section steel material. The geometric parameters of a rectangular tube are: length and width dimensions (generally expressed as width B and height H), wall thickness t, and length L, among which B, H, and t are more important. The symbol is generally represented as: BxHxtxL.

Angle steel

b - width of the short side; d - thickness of one side; r - radius of the inner arc; r1 - radius of the outer arc of one side;

Angle steel, commonly known as angle iron or triangular iron, is a long strip of steel with two sides perpendicular to each other, forming an angle. Angle steel is also divided into equal-sided angle steel and unequal-sided angle steel.

Its specifications are expressed in millimeters as side width x side width x side thickness.

Round pipe

B - length of one side; H - length of the longer side; R - radius of the outer arc; t - wall thickness;

A round pipe refers to a steel material with open ends and a hollow concentric circular cross-section, whose length is relatively large compared to its perimeter. Specifications are expressed using external dimensions (such as outer diameter or side length), inner diameter, and wall thickness. For pipe size descriptions, the first number always refers to the outer diameter; a pipe with an outer diameter of 219 mm is a pipe with an N200 (nominal diameter). The second number generally refers to the wall thickness.

Mastering steel structure fundamentals empowers you to select the right framing systems, specify proper connections, and anticipate load behaviors. Whether designing warehouses or high rises, these core principles remain your foundation. Start applying this knowledge to real projects. Efficient, safe, and cost effective steel construction begins with getting the basics right.

For more information needed or any inquiry,please feel free to contact Yumisteel team.