Large-Span Steel Structure Industrial Buildings
Large-span steel structure industrial buildings refer to industrial or public buildings that use steel structures as the primary load-bearing system, typically with spans exceeding 30 meters (the exact threshold may vary depending on industry standards and regulations). These buildings are characterized by open spaces, rapid construction, and strong adaptability, making them widely used in aviation manufacturing, logistics warehousing, sports stadiums, exhibition centers, and other fields. Below is a detailed analysis of large-span steel structure industrial buildings.
I. Key Features
Large-Span, Column-Free Space
Achieved through steel trusses, space frames, arch structures, or cable-suspended systems, allowing spans of over 100 meters without internal columns, facilitating flexible layouts for large equipment or zoning.
High Strength, Lightweight
Steel’s high strength-to-weight ratio reduces structural cross-sections and foundation loads, making it suitable for soft soil conditions.
Industrialized Construction
Prefabricated components are bolted or welded on-site, shortening construction time by 30%–50% compared to concrete structures.
High Expandability
Easy to extend (e.g., adding new bays) or relocate.
II. Common Structural Forms
| Structural Type | Applicable Span | Characteristics |
|---|---|---|
| Portal Frame | 15–36 m | Cost-effective, ideal for lightweight buildings, roof slope typically 5%–10%. |
| Steel Truss | 30–100 m | Triangular, trapezoidal, or parallel-chord configurations with top/bottom chords and web members. |
| Space Frame | 30–150 m | 3D load-bearing system (e.g., bolted ball-jointed grids), excellent seismic performance, suits complex roof shapes. |
| Arch Structure | 50–200 m | Load transfer via axial compression, aesthetically pleasing, used in stadiums/hangars. |
| Cable-Suspended | 100–300 m | Utilizes steel cables in tension, requires edge tension rings/anchorage (e.g., cable domes). |
III. Design Considerations
Load Analysis
Dead Loads: Roof panels, insulation, equipment pipelines.
Live Loads: Snow (uneven accumulation), wind (uplift critical for large roofs), crane loads (if applicable).
Special Loads: Seismic, thermal stress (expansion joints needed), equipment vibrations.
Stability Control
Buckling risk for compression members; slenderness ratio checks and bracing (e.g., horizontal/column bracing) required.
Geometric nonlinearity must be considered for single-layer lattice shells.
Joint Design
Rigid joints for critical connections (e.g., beam-column), pinned joints for truss supports.
Avoid stress concentrations; complex joints (e.g., cast steel) require FEM analysis.
Fire & Corrosion Protection
Fireproofing: Spray-applied fire-resistant coatings (1–3 hours rating), fireproof cladding per Code for Fire Protection Design of Buildings.
Corrosion Protection: Hot-dip galvanizing, epoxy zinc-rich primer + polyurethane topcoat; enhanced measures for coastal areas.
IV. Construction Process
Foundation
Isolated or pile foundations (for weak soil), anchor bolts pre-installed (±2 mm tolerance).
Steel Erection
Columns first, then roof; segmented lifting or integral sliding (e.g., for space frames).
Theodolite alignment (vertical tolerance ≤ H/1000).
Enclosure System
Roof: Corrugated steel sheet + thermal insulation (e.g., 75 mm rock wool) + waterproofing (min. 5% slope).
Walls: Sandwich panels or profiled sheets with ventilators/skylights.
Inspection
Weld UT testing (100% for Grade 1 welds), deflection check (≤ L/400).
V. Cost Optimization
Span Selection: Steel trusses for 30–50 m; space frames or beam-string structures for >60 m.
Material Choice: Q355B steel offers 20% higher strength than Q235B, reducing weight by 10%–15%.
Standardization: Uniform column spacing (e.g., 6 m/9 m), modular fabrication to minimize waste.
Maintenance: PVDF-coated panels (25+ years durability).
VI. Case Studies
Aircraft Hangar: 150 m arch roof + suspended cranes.
Logistics Hub: 60 m portal frame, 10-ton crane capacity.
PV Factory: 40 m lightweight steel roof with integrated solar panels.
VII. Common Issues
Excessive Deflection: Add prestressed cables or optimize truss depth (height-to-span ratio ≥ 1:10).
Condensation: Insufficient insulation or thermal bridging; check dew point.
Bolt Loosening: Regular torque inspections (esp. in high-vibration environments).
For further discussion on specific structural designs or construction cases, please provide detailed requirements!