HEB beams have excellent bending resistance due to their H - shape. The flanges (top and bottom) bear most of the bending stress, with their wide, thick design maximizing the section modulus (a key factor for bending strength). For example, HEB 300 has a section modulus of 917 cm³ (for major axis bending), much higher than smaller beams. This lets them withstand heavy vertical loads (like floor slabs, machinery) without excessive deflection, keeping structures straight and safe.
What's the corrosion resistance of uncoated HEB steel beams?
Uncoated HEB steel beams (made of carbon steel) have poor corrosion resistance. They react with moisture, oxygen, and chemicals (e.g., salt in coastal areas) to form rust, which weakens the steel over time. In dry, indoor environments, uncoated HEB can last years, but in outdoor, humid, or industrial areas, rust forms quickly. Thus, uncoated HEB needs regular maintenance (painting, oiling) to prevent corrosion, or coated versions (galvanized, painted) are used for harsh conditions.
How do HEB beams perform in seismic zones?
HEB beams perform well in seismic zones due to their ductility and strength. Made of mild or low - alloy steel (S235 - S355), they can bend and deform slightly during earthquakes without brittle failure, absorbing seismic energy. Their H - shape also ensures uniform stress distribution, reducing the risk of localized damage. When designed with proper connections (e.g., flexible joints), HEB - based structures can withstand seismic forces, making them suitable for earthquake - prone regions like Japan, Italy, or California.
What's the fire resistance performance of HEB steel beams?
Unprotected HEB steel beams lose strength at high temperatures-above 550°C, their strength drops sharply, risking structural collapse in fires. To improve fire resistance, they are often coated with intumescent paint (expands to form a heat - resistant layer), wrapped in fire - resistant boards, or encased in concrete. With these protections, HEB beams can meet fire resistance ratings (e.g., 60, 90 minutes), ensuring they maintain strength during fires, crucial for buildings like schools, hospitals, or high - rises.
What's the main use of HEB steel beams in commercial buildings?
In commercial buildings (offices, malls, hotels), HEB steel beams are mainly used for floor and roof framing. Their high strength supports heavy floor loads (people, furniture, equipment) and wide spans (up to 15m, reducing column use), creating open, flexible spaces. They also work in mezzanines and stairwells, providing stable support. Their light weight and space efficiency fit commercial designs that prioritize usability and aesthetics.
