The Column is one of the most critical structural members in a Ground Mounted Solar Module Mounting Structure (MMS). It supports the complete solar table and transfers all structural loads safely to the foundation. Every load acting on the Solar MMS, including the self-weight of the structure and wind forces, ultimately passes through the columns before reaching the ground.
In this article, we will understand the function of a Solar MMS Column, the different loads acting on it, how the load is transferred, the factors affecting column design, and the quality inspection requirements during installation.
Project Details
- Project Type
- Ground Mounted Solar Power Plant
- Structure Type
- Fixed Tilt Solar MMS
- Module Configuration
- 2P × 28
- Total Modules
- 56 Nos
- Module Size
- 2382 × 1134 × 35 mm
- Tilt Angle
- 11°
What Is a Column?
A Column is the primary vertical structural member of a Solar MMS. It supports the Rafters and transfers the entire structural load safely into the foundation or pile.
The Column acts as the main load-bearing member of the complete solar table.
Function of a Column
The Solar MMS Column performs the following functions.
- Supports the Rafters.
- Transfers Dead Load to the Foundation.
- Transfers Wind Load to the Foundation.
- Resists Compression.
- Resists Wind Uplift.
- Resists Horizontal Wind Force.
- Maintains the structural stability of the Solar MMS.
- Supports the entire solar table throughout its design life.
Load Transfer Mechanism
The load path of a Ground Mounted Solar MMS is shown below.
Solar Modules
↓
Hat Purlins
↓
Rafters
↓
Columns
↓
Foundation
↓
Soil
The Column is the final steel member that transfers all structural loads to the foundation.
Loads Acting on a Column
A Solar MMS Column is subjected to several types of structural loading.
Dead Load
Dead Load consists of
- Solar Modules
- Hat Purlins
- Rafters
- Self Weight of Column
Wind Pressure
Downward wind pressure increases the compression force in the column.
Wind Uplift
Wind uplift creates tension in the column and increases the uplift force on the foundation.
Horizontal Wind Force
Horizontal wind causes bending in the column and increases the demand on the bracing system.
Why Columns Are Important
The entire Solar MMS depends on the strength and stability of its columns.
A properly installed column
- Maintains the structural alignment.
- Transfers all structural loads safely.
- Reduces excessive deflection.
- Improves overall structural rigidity.
- Prevents excessive movement during high wind conditions.
Factors Affecting Column Design
The design of a Solar MMS Column depends on the following parameters.
- Height of Column.
- Number of Rafters Supported.
- Dead Load.
- Wind Pressure.
- Wind Uplift.
- Horizontal Wind Force.
- Foundation Type.
- Soil Bearing Capacity.
- Steel Grade.
- Section Profile.
Structural Actions on a Column
A Column may experience one or more of the following structural actions.
- Axial Compression.
- Axial Tension.
- Bending.
- Shear.
- Combined Axial Load and Bending.
Proper structural design should consider all governing loading conditions.
Importance of Column Alignment
Column alignment directly affects the installation quality of the entire Solar MMS.
Incorrect alignment may result in
- Uneven Rafter levels.
- Difficult module installation.
- Bolt hole mismatch.
- Additional bending in members.
- Increased structural stresses.
Quality Inspection Checklist
Before fixing the Rafters, verify the following.
□ Correct section profile.
□ Correct member length.
□ Vertical alignment.
□ Correct centre-to-centre spacing.
□ No visible bends or twists.
□ Galvanized coating intact.
□ Proper bolt tightening.
□ Proper foundation connection.
□ Correct elevation.
Foundation Connection
The Column should always be connected securely to the foundation.
The connection should provide adequate resistance against
- Compression.
- Wind Uplift.
- Horizontal Wind.
- Overturning.
The foundation connection should be inspected before erection of the remaining structural members.
Maintenance Checklist
During routine inspections, check the following.
- Corrosion.
- Loose bolts.
- Foundation settlement.
- Cracks around bolt holes.
- Galvanizing damage.
- Permanent bending.
- Misalignment.
Common Installation Mistakes
- Incorrect column spacing.
- Incorrect vertical alignment.
- Improper bolt tightening.
- Installing damaged members.
- Using incorrect foundation levels.
- Failure to check plumbness before fixing Rafters.
Best Practices
- Verify the survey coordinates before installation.
- Check centre-to-centre spacing of all columns.
- Confirm verticality using a plumb bob or digital level.
- Tighten all bolts according to the specified torque.
- Protect galvanized surfaces from damage during handling.
- Recheck alignment after installing Rafters.
Relationship Between Column and Other Members
Solar Module
Transfers load to the Hat Purlin.
Hat Purlin
Transfers load to the Rafter.
Rafter
Transfers load to the Column.
Column
Transfers load to the Foundation.
Foundation
Transfers load safely into the soil.
Conclusion
The Column is the primary vertical load-carrying member of a Ground Mounted Solar MMS. It receives all structural loads from the Rafters and transfers them safely to the foundation. Proper installation, accurate alignment, secure foundation connection and regular inspection are essential for achieving a safe, durable and long-lasting Solar Module Mounting Structure.
In the next article, we will understand the importance of Front Bracing, Rear Bracing and Wind Bracing, how they improve structural stability and how they resist lateral wind forces in a Ground Mounted Solar MMS.