IndiaCADworks Lifecycle BIM Process
Building Information Modeling (BIM) is often portrayed, particularly by those starting out on their BIM journey, as a software tool relating to the creation of graphical information only rather than depicting the entire collaborative design management data set.
This understanding is a misnomer which needs clarifying in two respects.
Firstly, BIM is a whole lifecycle process and necessarily involves the production, manipulation, and exchange of data through various levels of definition (or development).
Secondly, real collaborative BIM fuses the architecture-engineering-construction (AEC) sector with the AEC technology industry and offers multiple benefits throughout the lifecycle of a project. It allows the knowledge and tools from both of these areas to be used to make construction more efficient and to:
- Create a seamless collaborative process for all stakeholders involved in a construction project to work within a shared data environment, a centralized platform for graphical and non-graphical information generation
- Facilitate the extraction and incorporation of information through a single linked digital model or database
- Reduce conflicts, omissions, and errors and improve accuracy and quality
Level of Development (LOD)
Considering the first implication further, the two key components to the levels of definition (LOD) of a digital model are the levels of detail relating to graphical data of models and the levels of information relating to non-graphical data of models.
IndiaCADworks Approach to the LOD Specification Process
IndiaCADworks (ICW) develops its digital models in agreement with the American Institute of Architects (AIA) LOD Specification. It facilitates the collaboration of designers (architects and engineers), clients, project management consultants, sustainability consultants, cost consultants and contractors, facility management agencies and laser-scanning surveying companies.
BIMForum, the US chapter of buildingSMART, defines the LOD Specification as that which enables AEC industry practitioners to specify and articulate the content and reliability of digital models extremely clearly during the various stages of the design and construction process.
The LOD Specification defines and illustrates different building system model element features at different LOD - from LOD 100 through to LOD 500.
The critical phases of ICW’s approach to the BIM lifecycle are as follows and details of the appropriate LOD shown below each phase.
1) Inception-concept Design Phase
Throughout the inception-concept design phase (the equivalent of LOD 100/200) design consultants collaborate in the creation of a digital model from their respective disciplines. This process enables conceptual design representation.
2) Detailed Design Phase
As a project moves through a subsequent detailed design phase (the equivalent of LOD300) clash detection is performed collaboratively to generate a clash-free federated digital model. This model acts as a scaled representation of a facility incorporating detailed design geometrical information and is used to produce coordinated detailed design information. Used for visualization applications, enhanced as necessary by VR, to express the design intent to a client. They can navigate around the building to understand and finalize the design to reduce the need for any subsequent change order. Constructability issues can be identified and resolved through this model, and it can be used to extract quantities in any desired format for the bill of quantity generation. 4D project simulation is generated by linking the construction schedule with the digital model to provide time-based construction activity sequencing.
3) Procurement / Construction (Execution) phase
The digital models then transferred to the contractor at the onset of the implementation phase (the equivalent of LOD400). The contractor has the responsibility of upgrading the model for it to represent site conditions and of integrating new changes and inputs by the subcontractors into the model, if not already incorporated during earlier stages.
The federated model upgraded by adding all the necessary construction details. This phase deals with details from the participating subcontractors (elevator contractor, façade contractor and so on) along with geometric information that allows the generation of shop drawings from it (expansion joints, stiffener columns and such like).
This process may involve the generation of custom families in the federated model to suit approved material submittals for different trade components (such as plumbing fixtures, doors and so on). Often manufacturers provide BIM objects for the main contractor are integrated into the Civil BIM Model of a facility.
Clash-free and coordinated drawings are generated from the model for use on-site during this phase. The model also includes site instructions, engineer’s revisions, and on-site changes. This change leads to the development of a digital model which contains all information present in the design drawings as well as other documented information generated on-site.
Updated construction baselines can be linked with the digital model to provide a comparison of the planned as well as actual on site conditions. This process is what is known as creating a "digital twin."
4) Close Out and Beyond (Completion of Execution, Post Commissioning) phase
The digital model of Close Out and Beyond (Completion of Execution, Post Commissioning) phase ((the equivalent of LOD500) can be a field verified representation of the model from the previous phase. During this time the model is expected to be accurate to enable operation and maintenance of the building to be carried out using the information within it.
It should contain all the information mentioned in the submittals as as-built conditions.
If needed, a geometrical as-built accuracy of the digital model is obtained either by being upgraded and modified concerning the red mark-up drawings received or done using laser-scanning where the model verified for unincorporated on-site changes. Once geometrically audited, all non-graphical information regarding different building components can be added to provide a single source of information and specifications for the facility by adding the submittal information and attaching product specification PDFs in the model.