Main Reinforcement Methods for Purlins in Steel Structure Workshop

I. Adding Supports and Auxiliary Components

1.Reinforcement with Angle Braces and Hoop ClampsAdd angle braces at the eccentric or deflected parts of purlins under load, or install hoop clamps on purlins to enhance local stability.

2.Installation of Tie RodsWhen the span is greater than 4m, install tie rods at the mid-span position between purlins.When the span is greater than 6m, add an additional tie rod at each trisection point to prevent lateral instability.

II. Changing Cross-sections and Structures

1.Cross-section ReinforcementIncrease the cross-sectional dimensions of purlins (e.g., thicken the flange) to improve load-bearing capacity.Reinforce weak parts by welding or bolt connection to ensure a reasonable force transmission path.

2.Continuous Support SystemConvert the original simply-supported purlins into a continuous support system (e.g., changing simply-supported to continuous) to enhance overall stability.

III. Optimizing Load Distribution and Node Design

1.Adjusting Load DistributionReduce the slenderness ratio of components and improve dynamic performance by adding intermediate supports or changing the support method.

2.Node StrengtheningStrengthen the connection nodes between purlins, columns and beams to ensure the coordinated work of steel roof trusses and skylight frames.

IV. Prestressing and Construction Technology

1.Prestressed ReinforcementApply prestressed tie rods at key parts to improve structural stiffness.

2.Welding Process ControlAvoid welding under load conditions and prioritize reinforcing weak parts. Adopt alternative measures when welding is not suitable for small angle steels, round steels and other components.

V. Checking Calculation and Safety Control

1.Stability Checking CalculationBased on the actual stress condition of purlins, adopt the calculation formula for overall stability or deformation checking to ensure compliance with safety standards.

2.Allowable Deflection ControlFollow the values specified in the code (e.g., the allowable deflection of simply-supported Z-shaped section purlins at both ends shall be ≤ 5mm) to avoid excessive deformation.

Conclusion: The reinforcement scheme should be combined with the purlin span, load type and the characteristics of the original structure. Priority should be given to improving safety by adding supports, optimizing cross-sections and adopting reasonable construction technologies. Meanwhile, strict checking calculation shall be carried out to ensure compliance with code requirements.