Case Study: 3D scanning for heritage listed sites in Australia
Surveying a heritage listed site using 3D scanning
Realserve, who provide surveying services in Sydney, was engaged by Sydney Living Museums (recently renamed to Museums of History New South Wales) to conduct an extensive survey, using a mixture of techniques, to document a 19.5Ha heritage listed site. While traditional 2D survey drawings may have delivered modern documented drawings, the use of 3D scanning of such large sites can provide a more extensive library of digital documentation that can be used for many different purposes.
A surveyor in Sydney can use 3D scanning tools to capture an entire block of land, including any structures that are on it. Once the external area has been scanned, we can then continue to 3D scan the internal of each structure as well so that every millimetre of the site is captured.
While our surveyors will typically focus on 3D scanning of buildings, when it comes to a heritage site we can also capture the topography of the land the buildings sit on, remains of any ruins or other items located on the site. With all of that information at hand it can be used for refurbishments, repairs, adding visitor specific structures like walkways or simply to document the site to keep track of changes over its lifespan.
The data captured from a 3D scan is extremely accurate, to the millimetre in fact, and this data can be used to create a Point Cloud which can be used to create any type of 2D drawing documentation or used to build a Revit model to be used in 3D design tools.
See the real site in the video from Museums of History New South Wales
Can a heritage site be 3D scanned to present an aerial perspective of a site?
3D scanning is a non-destructive way of capturing a digital real world representations of buildings or building sites. With the ability to measure fine details and capture free-form shapes, 3D scanners can generate highly accurate point cloud data of the most complex buildings or locations. This includes factories, offices or even heritage listed buildings that have intricate details.
From a scan, registration and processing, 2D and 3D models can be generated using 3rd party software to achieve a deliverable specific to your needs from land based 3D scanners or even aerial drone mounted units. Literally the sky is the limit because we can laser 3D scan a whole block of land with buildings on the site from the air to then compliment ground based or internal scans.
IDrone based imagery can be processed using photogrammetry to produce a point cloud which can then be combined with the information gathered from each building so there is a full visualisation, interrogation, design, modelling and analysis available. This is the ideal way to create documentation for heritage listed building sites in Australia.
Our surveyors have the ability to combine traditional survey practices, terrestrial 3D scanning and remote piloted aircraft to collect all the required data (even for a huge site like this which is bigger than 19Ha). All of the data was provided as a 3D point cloud and Revit model in MGA 2020 AHD with coordinates of the entire site
How did we survey this heritage listed site?
As mentioned we used a combination of traditional survey practices, terrestrial 3D scanning and remote piloted aircraft to collect all the data. We used a combination of scanning tools that included;
- A Leica TS11 total Station
- A Leica RTC360
- A Leica BLK360
- A DJI Matrice 300 RTK
Ensuring accuracy across such a large heritage listed site was one of the challenges presented to us for this project. To overcome this obstacle our survey division set up an accurate control network across the entire estate from which we would be able to link back into and provide control for our terrestrial and RPA 3D data.
This control network also allowed us to register the 3D data in sections (rather than all at once) and combine at the end (as it was in the same coordinate system – MGA56 2020). This allowed our team to process all the data more efficiently.
Once a point cloud is created how can a heritage site use the information
By conducting a survey of the site using 3D scanning tools you can walk away with millions of data points that can create a point cloud of the building. This millimetre perfect data can then be manipulated in many different ways to create traditional 2D documentation or a Revit Model.
This makes it very simple for a heritage listed site to receive consideration for refurbishment, renovation, remodelling or getting modern structural elements added to aid day to day usage, preservation or even tourism. While a 3D scan will capture much more detail than will generally be required, it is the most comprehensive way to have data available for any type of use in the future. There would be no need for repeated surveying visits or for new measurements to be taken, the 3D scanner picks up every single detail.
Best of all this type of surveying process uses such advanced capture technologies that it can work in low-light and no-light conditions, inside or out, to ensure you get the information you need for a project whether it is an old heritage building or a modern structure. With millions of data points from various perspectives, the photorealistic representation of reality can be used by interior designers, steel detailers, an architect or historian to use for their required purposes.
It means traditional 2D documentation can be created including;
- Existing Conditions Floor Plans
- Reflected Ceiling Plans
- Cross-sectional Plans
In addition to its practical applications, point cloud technology also enables a level of preservation that was previously impossible. By creating a digital replica of a heritage building, architects and preservationists can ensure that the building’s unique features and historical significance are recorded and protected for future generations.
Reverse engineering is also made easier through point cloud technology, allowing for the recreation of missing or damaged elements of heritage buildings. By using the 3D data, architects and engineers can accurately recreate elements such as ornate moldings, intricate sculptures, and decorative fixtures, restoring the building to its original glory.
Point cloud technology has revolutionised the way heritage buildings are preserved and restored, providing accurate and comprehensive data that supports both practical and artistic applications.
Using a Revit Model for a heritage site
A Revit Model was required for this surveying project. The point cloud information captured in this project was can used to create a Revit Model of the existing conditions. This electronic representation can be viewed, shared and manipulated by multiple stakeholders so that variations of a renovation or the addition of structural elements can be considered. Any changes made to the model will be reflected across all the electronic documentation and for all stakeholders to view, no matter where they are located.
A 3D revit model can be created by an architect to design with. Using a Revit model allows for entire buildings or parts of buildings to be modelled and worked on electronically. This can be very useful for multiple parties to collaborate with who are all involved in a rejuvenation project for historic buildings. Using Revit modelling as part of the BIM process makes it easier to create & manage things like 3D renders, 3D perspectives, detailed drawings and walkthroughs where any changes are then ‘updated’ across all documentation.
The use of the latest 3D scanning technology allows for electronic documentation that facilitates collaboration among various stakeholders involved in a construction project, including council and government agencies. The Revit model can be used to develop a Digital Twin, which is a virtual documentation of a building, process or systems and can be used to simulate different scenarios in a virtual environment.
Digital Twins can aid in ensuring that future developments and plans suit the requirements of the site, local heritage development laws and the goals of a project. Different variations and designs can easily be created which can be used for simulating outcomes, estimating costs, creating proposals or comparing the complexity of different solutions.
Digital Twins are increasingly being created for City planning and management purposes. This can not be done without the 3D model, captured with 3D laser scanners.: A digital twin of a building, and furthermore, a city, can be used to simulate and test different scenarios for urban planning and management, such as testing the impact of new transportation systems or infrastructure projects on traffic flow and air quality.
There are so many additional uses of accurate 3D Revit models including:
- Tender scoping
- Pre-construction / renovation as-built assessments
- Building Information Modelling (BIM)
- Virtual Design Construction (VDC)
- Quality Control during a renovation of construction project
- Field annotation and dimensioning
- Process comparison and clash detection i.e. design vs construction