Welded H beams are made by joining steel plates via submerged arc welding (SAW) for deep penetration. This allows custom sizes (e.g., 400x400x13x21) beyond standard hot-rolled dimensions. Welded beams have tighter tolerances and can use high-strength alloys like A572 Grade 50. They are ideal for specialized projects like industrial cranes. Post-weld heat treatment eliminates residual stresses.
What standards apply to EN10025 H beams in Europe?
EN10025 H beams comply with EU norms for chemical composition (e.g., S275JR/S355JR) and mechanical properties. Testing includes Charpy impact tests at -20°C for cold resistance. Beams must meet dimensional tolerances per EN 10034. CE marking ensures compliance with the Construction Products Regulation (CPR). These standards are harmonized across 30+ countries.
How do H beams perform in seismic zones compared to concrete beams?
H beams absorb seismic energy through ductility, reducing collapse risk during earthquakes. Their lightweight nature lowers inertial forces, unlike brittle concrete beams. Connections with slotted holes allow movement, while concrete requires costly reinforcement. Retrofitting existing structures with H beams is faster and more economical. Japan's seismic codes heavily favor steel H beams for high-rises.
What are the key uses of H piles (HP shapes) in foundation systems?
H piles (e.g., HP 310x125) transfer structural loads through weak soil to stable bedrock. Their high section modulus resists bending during driving. Common in skyscrapers and bridges, they reduce settlement risks. Corrosion-resistant coatings like epoxy are applied for longevity. HP piles can be spliced for depths exceeding 50 meters.
How to select between universal beams (UB) and H beams for a project?
UB beams (e.g., UB 203x133) have tapered flanges for lighter loads, while H beams (e.g., HEA 300) offer uniform thickness for heavy-duty use. UB beams are cheaper for residential frames, whereas H beams suit industrial halls. Consider span length-H beams excel beyond 10 meters. Always verify local building codes for material approvals.