Scan to BIM: Accurate, Fast, and Sustainable Demolition Projects

The AEC community has long reaped the benefits of Building Information Modeling (BIM) in construction planning, monitoring, and project management. More recently, many have begun to apply BIM to the deconstruction and demolition phase to analyze existing conditions, identify reusable elements, and plan deconstruction.

 Image credit: https://unsplash.com/@markkoenig 

In a unique case study of deconstructing a nursing home in the Netherlands, the project team used BIM-based methodologies to explore how a structure's end-of-life can be reorganized to be more efficient and sustainable. Using BIM, an accurate as-built 3D model was created to replace dated 2D design drawings. Then, reusable elements were labelled using 3D text in the virtual environment to prevent errors that could arise from hand-written codes onsite. Finally, the proper deconstruction activities were planned by visualizing the sequenced deconstruction of the nursing home in 3D over time.

In another Australian study, researchers examined the potential of using BIM to improve construction and demolition waste (C&DW) management, citing the inadequate use of digital tools and construction technologies as a main hindrance in its implementation.

 Figure: Visual process map of BIM integration in demolition waste management process.

Source: Han D, Kalantari M, Rajabifard A. Building Information Modeling (BIM) for Construction and Demolition Waste Management in Australia: A Research Agenda. Sustainability. 2021; 13(23):12983. https://doi.org/10.3390/su132312983

To fully capitalize on what BIM has to offer for C&D waste management, Han et al. proposed 3 research areas:

• Improve data acquisition efficiency and quality with diverse tools.
• Automate point cloud to BIM conversion using optimized algorithms.
• Extend BIM-based sustainability analysis to the DWM domain with enhanced data schema and material databases.

Within the plethora of tools available on the market, handheld 3D laser scanners are a great choice for building surveyors, inspectors, and structural engineers to capture and analyze building data for efficient post-processing and BIM creation.

Current Pain Points - Traditional Survey Methods

Traditional property surveys rely heavily on distance measurement equipment like laser rangefinders and total stations, which require significant labor and resources. Multiple teams may be required to work onsite, recording measurements manually, and then spend copious amounts of time creating digital drawings based on hand-drawn sketches, resulting in low efficiency and a higher risk of errors.

Benefits of Handheld 3D Laser Scanners

Handheld 3D laser scanners like the FJD Trion S1 can help surveyors mitigate traditional limitations by enabling contactless, fast, and high-accuracy building scans. A simple, brisk walk around the building with the scanner will render point cloud models in real-time, which can then be seamlessly imported into a post-processing software to generate 2D floor plans, at the LOD and LOA required by the client.

Workflow Overview

1. Data Capture (FJD Trion S1)
2. Point Cloud Processing and Optimization (FJD Trion Model)
3. Create 2D Floor plans (FJD Trion Model)
4. Create BIM (Autodesk Revit)

Case Study: Factory Demolition Survey

Let's take a look at a project involving the demolition of an abandoned factory site. The goal was to create floor plans and a BIM model to calculate the demolition volume.

Data Capture

1. 1. First, the surveyor planned his walking path to ensure data capture can be done in one go, and that there's enough overlap at the beginning and end of the capture session to ensure loop closure.
   2. A floor-by-floor survey was conducted of the target structure.
   3. A point cloud preview was available in real-time in FJD Trion Scan.

Scanning Time: Approx. 5 hours

Point Cloud Processing and Optimization

The scan results were imported into the FJD Trion Model software for point cloud segmentation, noise removal, and stitching to create a complete point cloud data set.

Processing Time: Approx. 30 minutes

2D Floor Plan Generation

Relevant floor levels were selected in the FJD Trion Model for automatic contour extraction and 2D floor plan generation, followed by editing and optimization to produce DXF floor plan drawings.

Processing Time: Approx. 30 minutes

BIM Creation

Using BIM software like Autodesk Revit, walls, beams, and columns were built based on the point cloud model. After completing the BIM model, the visualization was inspected in a rendering software.

Processing Time: Approx. 2 hours

Benefits of the FJD Trion S1 Solution

Efficiency Comparison

 

The 3D laser scanner was 9 times more efficient compared to laser rangefinders, saving time and costs.

Accuracy Comparison

 

The 3D laser scanner data had a relative error within 5 cm, meeting industry and project requirements.

Final Thoughts

 


Employing the FJD Trion S1 3D laser scanner resulted in a ninefold improvement in overall efficiency, significantly reducing labor intensity and human resource costs. The level of accuracy met the requirements of building demolition and completion. Additionally, the point cloud model was filed away as part of the building's permanent record, enabling easy access for future project collaborators.

Advancing Property Surveys with 3D Laser Scanning

In this project, the FJD Trion S1 3D laser scanner captured point cloud models of the factory in just 5 short hours. The ability to visualize the data capture in real-time while the operator was walking enabled the precise and comprehensive documentation of the three-dimensional space. This approach allows surveyors to quickly generate floor plans, elevation models, and BIM right in the processing software. The point cloud data obtained from the scans can also be imported into platforms like Autodesk 3ds Max or Revit for BIM creation, expanding the range of data applications.

In conclusion, there is a lot of untapped potential for BIM use in building demolition. Operators can streamline property surveying workflows with handheld 3D laser scanners to capture data quickly, process effortlessly, and obtain accurate results. The adoption of these technologies not only improves demolition process but also ensures sustainable construction practices by optimizing the use of resources and reducing waste.

Learn more about  FJD Trion S1 and  FJD Trion Model.