Modeling and Clash Detection for Bridge Cranes in Revit

Modeling Bridge Cranes in Revit

Bridge cranes are an essential material handling system used in many industrial facilities. Modeling bridge cranes in Revit can be a complex process, but is vital for clash detection, quantity takeoffs, and fabrication. This article will provide a step-by-step workflow for efficiently modeling bridge cranes in Revit.

Importing Bridge Crane Families

The first step is importing or loading the proper Revit families for bridge cranes. Many content libraries include bridge crane families, or you can model your own custom families. Key components that need families include the bridge, end trucks, trolley, and hoist. The families should be properly parameterized so capacities, dimensions, and other data can be adjusted.

Laying Out the Crane Bridge

Once families are loaded, you can begin laying out the bridge crane. This includes placing crane girders, beams, joists, rail supports, and the end truck families. The end truck families should snap to the building column families. Use proper dimensions from the equipment drawings when available. For clearance requirements, include non-structural elements for any warning bumpers on the crane bridge.

Adding the Trolley and Hoist

Next, load the trolley family at mid-span of the crane bridge. This is the moving machinery component that runs along the length of the bridge beams. The hoist or lift family can be connected below the trolley. Make sure these align with the shop drawings. Properly constrain so the trolley travels along the full bridge span.

Incorporating Supplemental Steel

Model any supplemental steel that supports the crane, including brace frames, base plates, anchor rods, and connections. Structural steel can be imported from CAD or modeled directly in Revit. Include any wall or column reinforcing required to carry crane loads. Proper detailing is crucial for constructability.

Adding Lifting Attachments

Optionally, the hoist tool can be modeled. This includes slings, hooks, rigging, and any custom lifting attachments. This allows for visualization of the lifting arrangement. Include model elements for power supplies, control pendants, lighting, and maintenance access platforms if needed.

Classifying and Documenting

Apply classification data to the crane components. Include information like equipment tags, descriptions, manufacturers, capacities, power supply specs, etc. Create plan region views, details, and sections as needed for documentation. Generate assembly sheets for approval by the equipment vendor or QA/QC.

Clash Detection with Cranes

Executing clash detection with the modeled bridge crane is critical. Clashes can be detected within the crane itself or against other building components. Common clashes include inadequate column and beam clearances, intersecting utilities or ductwork, low haunches or soffits, and equipment access issues.

Crane-to-Crane Clashes

For facilities with multiple cranes, clash detection should be run crane-to-crane. Adjacent or overlapping cranes may clash at the bridge, trolleys, or hoists depending on spacing and travel paths. Adjust positions to maintain proper clearances between cranes.

Other Clash Types

Lighting, cable trays, pipes, conduits, and any overhead MEP components should be included in clash detection. Collision checking the crane through its full hook travel envelope is vital. Clashes can cause construction delays and safety issues if not addressed before installation.

Using Cranes for Lift Planning

The detailed Revit crane models can also be used for lift planning on the job site. This helps visualize the lifting maneuvers, rigging arrangement, tagline locations, and equipment access. Accurate lift plans may be required by the owner or contractor before allowing cranes on site.

Lift Path Simulation

With the crane model in place, the hoist position and lift path can be simulated. This helps determine the optimal hook height and reach based on load weight and dimensions. The software can dynamically update lift parameters as the hoist position changes.

Improving Safety

Detailed lift planning identifies potential hazards so the contractor can install proper guarding and barriers. This prevents collisions between loads, cranes, and adjacent work. Correct lift angles, boom length, counterweight, and outrigger spans are also confirmed resulting in safer lifts.

Conclusion

As shown above, Revit provides an efficient way for industrial builders to model bridge cranes. This enables coordination with other disciplines, reduces costly field issues, improves safety, and aids in fabrication and installation. Taking the time to properly model cranes in Revit using accurate component families is crucial for project success.

FAQs

What are the key components that need Revit families for modeling a bridge crane?

The key components that need Revit families include the bridge, end trucks, trolley, and hoist. Additional components like lighting, control pendants, and maintenance platforms may also require families.

What is the benefit of clash detection with the modeled cranes in Revit?

Executing clash detection can identify collisions between crane components, adjacent cranes, overhead MEP utilities, and other building elements. This prevents costly field coordination problems and safety issues.

How can the crane model be used for construction lift planning?

The models enable simulation of crane lifts by visualizing the hook travel path, required boom/jib lengths, rigging arrangements, and optimal hook height. This results in safer lift plans submitted to the contractor.

What are some potential crane-related clashes to check in Revit?

Some potential clashes include inadequate column or beam clearances, intersections with ducts/pipes, low haunches near the crane, intrusions into the hook travel envelope, and issues with lighting or cable trays above the crane.