The Challenge
AsBuilt was contracted by a power generation facility to perform laser scanning, 3D modeling, and 2D drawing development for a section of new Primary Air (PA) ductwork. The project required scanning an existing PA duct run extending from the base slab to the 4th-floor elevation to support future engineering and upgrade planning.
The vertical span covered multiple structural levels within a dense mechanical environment, including structural steel, platforms, equipment, piping, and utilities. Accurate existing-condition data was critical to:
- Support future duct modifications or replacement
- Validate structural clearances and tie-in locations
- Identify interferences across multiple elevations
- Reduce risk in retrofit design
- Provide engineering-ready documentation
Legacy drawings did not fully reflect field conditions, increasing the potential for clashes and costly design revisions.
The Solution
High-Resolution Laser Scanning
AsBuilt conducted a detailed terrestrial laser scan (LiDAR) of the designated PA duct section from grade to the 4th floor. The scan captured:
- Existing primary air duct geometry
- Structural steel framing and supports
- Access platforms and stairways
- Adjacent piping and utilities
- Equipment within proximity to the duct run
The scan data was processed into a registered, high-accuracy point cloud, providing a complete digital representation of the vertical duct section.
3D Modeling & Verification
Using the point cloud as a reference, AsBuilt developed accurate 3D models representing:
- Primary air ductwork
- Structural members
- Major utilities and surrounding components
Each modeled element was verified against the point cloud to ensure dimensional accuracy and alignment. The final 3D model was delivered in the client’s required format for engineering integration and future planning.
2D Engineering Drawings
In addition to the 3D model, AsBuilt produced detailed 2D drawings derived directly from the verified model, including:
- General arrangement (GA) drawings
- Isometric views of the PA duct section
- Elevation-based representations for multi-level reference
These drawings provided engineering teams with clear documentation for design development, constructability review, and future modification planning.
Deliverables
- 3D laser scan and registered point cloud
- Verified 3D model of PA duct and surrounding structures
- 2D general arrangement drawings
- 2D isometric views
Results & Impact
The project delivered accurate, multi-level as-built documentation to support future primary air duct modifications within an active power plant. By leveraging laser scanning and model-based verification, AsBuilt reduced engineering uncertainty, minimized retrofit risk, and provided reliable data for long-term infrastructure planning.
