Contact Info
+98 21 2691 9361+98 21 2691 9439
Email: info@pvada.co
Address
No. 7, N Qalandari St, Qeytarieh
Tehran, 1931743115, IRAN.
Think Outside the Box
When we talk about Scan to BIM, we talk about a process and series of steps that we implement to get an actual representation of the existing conditions of a project. We may question its applicability and who can use this process.
The B1M, construction’s leading video channel, defines Scan to BIM as The process of 3D laser scanning a physical space or site to create an accurate digital representation of it. This representation can then be used for designing, assessing progress or evaluating option.
So keeping it brief, when we have an existing building in place and we want to bring some alterations like retrofitting, renovation, refurbishment, or reconstruction; where we aim to keep the established structure and system in place. In that scenario, it is very important to have a detailed and accurate representation of the existing conditions of the building. A 3D laser scanning device is used to capture the existing conditions, the scanned data is in the form of “Points” when millions of such points are combined together that formulate a Point Cloud Scan. A Point Cloud Scan is then imported into a 3D Modeling platform with the purpose of creating an As-built model.
The intended use of the Scan to BIM process can be for: site verification, design validation/planning/comparison, develop as-built drawings, interference checks, MEP or construction elements demolition, or addition, documentation of existing building conditions, quantity take-off, and budget estimation. In the process of documentation, the following are levels of documentation:
Level 1: Floor Plans
Level 2: Exterior Elevation & Roof Plans
Level 3: Sections
Level 4: Site Plan Layout
Execution of a Scan to BIM project can be very challenging, to implement the project successfully we have made a step-by-step process, which is described below and involves four steps [1] Capture [2] Process [3] BIM Modeling and, [4] Quality Assurance and all four steps should be executed as per BIM Execution Plan (BEP/BXP) and as per project workflow.
Point Cloud to BIM
Don’t have the time to read the whole blog?
you can download and read it at your convenient time.
1. Capture
1
In this phase, we gather as much information we can gather from the field and from the client about the project. We define the Scope of Work (SOW) at this stage, Level of Detail (LOD), timeline, and a deadline for the project. It is very important to have a descriptive Scope of Work (SOW) because that will define the inclusion and exclusion of all the trades. For a Scan to BIM project, capturing of the information takes place in two phases.
(i) Pre-Mobilization Considerations
(ii) On-Site Information
2. Process
2
After, capturing the as-built conditions of the building, the next step is to process the scan. This is a very important step which includes validating the survey data regardless of its accuracy. Inspection of the scan should be performed to check the interruptions in the fluidity of the data, which may be caused by an environmental vibration and may not be caught by internal system checks. In order to process the scan data, it is important to break the datasets into clusters and to always keep a copy of data prior to any manipulation.
Next comes post-registration of the scan data. Here, the alignment of the data plays a major role. The different applications can require different techniques to align like- best fit, ortho, geo-referencing, etc. One should always manually check the scan data to avoid any kind of overlapping or any error. A Point Cloud Scan may seem to be dirty or noisy which may be difficult to correct the elements. So the initial setup is important to register and load the point cloud scan completely.
3. BIM Modeling
3
Modeling is where the Point Cloud, a real-life scan of the project gets shape in a digital platform. To model the Point Cloud Scan, several steps need to be followed from Verification of the Point Cloud Scan, Project Information to File Insertion in Revit, and File Set Up. These steps are described below:
(i) Verification
(ii) Insertion
(iii) File Set-Up
(iv) Modeling
(v) Collaboration
4. Quality Assurance
4
There are few QC process steps to be followed after modeling in order to ensure the quality of the model. Firstly, run a quick round of model check by throwing a section and move it across the project. By using the visibility and override options to check on specified elements. It is advised to do a thorough comparison of a delimitated area by using Plan, Section, or 3D view. To check the clashes between Mechanical, Electrical, and Plumbing disciplines, use Autodesk’s Navisworks as it provides a lighter and easier way to navigate a Revit Model. It is very important to clean the file to delete all the reference points and detailed lines from the model.
09
Explore our extensive range of BIM services tailored to meet the needs of AEC professionals
share on