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Jul 22 2025
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During the installation of steel structures, various problems may arise due to construction processes, material quality, environmental factors, and other influences. Below are common issues and their preventive measures to ensure project quality, safety, and progress.
Common Issues:
Columns and beams exceeding vertical/horizontal tolerance
Misaligned bolt holes, preventing proper alignment
Overall structural deformation (e.g., frame twisting or tilting)
Preventive Measures:
1. Before Construction:
For steel structures, use total stations and laser levels for precise layout to ensure the accurate positioning of embedded foundation parts.
Inspect component dimensions, especially bolt holes, to avoid factory errors.
2. During Installation:
Use jacks and guy wires to adjust component positions, ensuring vertical deviation ≤ H/1000 and ≤10mm.
Employ temporary supports to secure steel beams and columns, preventing collapse or displacement.
3. Inspection Phase:
Verify installation accuracy with theodolites and spirit levels to ensure compliance with GB 50205 standards.
Common Issues:
Lack of fusion, slag inclusion, or porosity in welds
Welding deformation leading to structural instability
Weld cracks (cold cracks, hot cracks)
Preventive Measures:
1. Pre-Welding Control:
Select qualified welders (certified) and use appropriate Welding Procedure Specifications (WPS).
Clean weld joints, removing oil, rust, and ensuring proper groove angles.
2. Welding Process Control:
Use symmetrical welding and back-step welding to minimize deformation.
Control interpass temperature to avoid rapid cooling-induced cracks.
3. Post-Welding Inspection:
Conduct non-destructive testing (UT/RT/MT) to ensure weld quality.
Apply flame or mechanical correction to deformed areas.
Common Issues:
Insufficient bolt tightening (low torque)
Misaligned bolt holes, forced reaming
Bolt corrosion or missing washers
Preventive Measures:
1. Pre-Installation Inspection:
Ensure bolts, nuts, and washers are matched and free from rust or damage.
Use test pins to check bolt hole alignment; forced reaming is prohibited.
2. Tightening Process Control:
Apply torque wrenches according to specifications (initial tightening → final tightening).
Final torque values for high-strength bolt assemblies must meet design requirements.
3. Inspection:
Use torque-checking wrenches to sample 10% of bolts, ensuring proper tightness.
Common Issues:
Coating damage leading to steel corrosion
Fireproof coating peeling or insufficient thickness
Inadequate corrosion protection at welds and bolt connections
Preventive Measures:
1. Corrosion Protection:
Inspect coating integrity before installation; repair damaged areas (sandblasting → primer → topcoat).
Apply additional protection (e.g., sealant) to bolt connections and welds.
2. Fire Protection:
Clean surfaces before applying fireproof coatings to ensure adhesion.
Use thickness gauges to verify coating thickness meets fire resistance requirements.
Common Issues:
Component deformation or falling during lifting
Crane tipping or overloading
Workers not wearing safety harnesses at heights
Preventive Measures:
1. Lifting Plan Optimization:
Calculate component center of gravity and select proper lifting points (avoid eccentric loads).
Use spreader beams or multiple cranes to prevent deformation.
2. Safety Management:
Only certified operators may use cranes; overloading is strictly prohibited.
Workers must wear safety harnesses and fall arresters; install safety nets.
3. Emergency Preparedness:
Halt lifting operations in extreme weather (high winds, heavy rain).
Establish restricted zones to prevent unauthorized access.
Common Issues:
Poor welding quality in winter (low-temperature brittleness)
Accelerated steel corrosion in rainy seasons
Poor coating curing in high temperatures
Preventive Measures:
1. Winter Construction:
Use low-temperature electrodes and preheat joints (100–150°C).
Set up heated enclosures to maintain welding environment ≥5°C.
2. Rainy Season Construction:
Elevate steel storage to prevent water accumulation and rust.
Dry electrodes before welding to avoid hydrogen-induced cracks.
3. High-Temperature Construction:
Avoid painting under direct sunlight; schedule work during cooler hours.
Monitor coating curing time to prevent sagging or blistering.
The key to successful steel structure installation lies in precise measurement, standardized welding, reliable connections, strict corrosion protection, and safe lifting practices. Through scientific management and preventive measures, quality issues can be effectively avoided, ensuring safe and efficient project completion.
