【BIM】CCBM 學習筆記 (Part 9) - 建築資訊模型 Building information modeling (BIM) - 簡單的回答幾個你所關心的問題 (一) Answers to the Questions You May Concern - Part 1

A1. What do you think are the value, limitations and challenges of adopting BIM in the practical project?

• Value of adopting BIM:

From my personal experience of BIM application in E&M installation and construction management, BIM generates 3D models, making it easier for clients, contractors, and designers to visualize the plant room arrangement of all MEP (mechanical, electrical, plumbing) equipment. In the coordination meeting, BIM can be used for easily presenting the location, spacing, dimensions of all building service provisions, which enhances the collaborative working

• Limitations and challenges of adopting BIM:

The BIM model currently applied in Hong Kong’s projects is usually constructed by a BIM modeller, instead of a professional engineer. Such a BIM modeller is not capable of any working experience in practical engineering design or construction works. BIM relies on accurate data input. From my personal experience in E&M BIM review, I always found lots of errors on the information included in the BIM model, such as precise dimension/size of the equipment, and incomplete connections between the air ducts, pipes, and cable containment. The lack of BIM-trained professionals is currently a challenge for BIM applications in Hong Kong

A2. What is your expectation of BIM in the next decade of the AECO industry?

BIM is expected to continue its rapid growth in the AECO industry over the next decade, focusing on increasing interoperability and integrating AI-driven insights. 

BIM is expected to evolve from a design tool to an integrated practice for all stakeholders, improving collaboration and communication and reducing errors and rework. Artificial intelligence is likely to play a key role in this evolution, I expect AI will take over most of the repeat and meaningless works and tasks in design and management, such as data/information input and output for the BIM model. For example, AI, by analysing the information in the BIM model, could streamline workflows, help with complex decision-making, and automate menial tasks to improve efficiency and accuracy throughout the building lifecycle. In construction, AI could manage logistics, oversee quality control, and automate tasks to alleviate labour shortages and improve safety. On the operational side, AI could analyse energy efficiency data, predict maintenance needs, and optimize facility management to ensure sustainable building functionality throughout the lifecycle. 

A3. Share some experience on the BIM-related standards and guidelines in local & global contexts and state their purposes and utility stage?

In Hong Kong, the Construction Industry Council (CIC) has developed comprehensive BIM standards, such as the CIC BIM Standards - General (Version 2.1 - 2021). From my practical working experiences, Airport Authority Hong Kong (AAHK) has its own specification of BIM Standards, which provides a unified foundation for authoring, storage and sharing BIM content. It contains structured guidelines for how to create, locate, name, edit, and publish BIM in the context of all parties’ collaboration. Specific to requirements to implement Level 2 BIM for Airport Authority Hong Kong (AAHK) Projects, this standard document can be adopted towards all future AAHK projects utilising BIM.

AAHK has embraced BIM for its airport infrastructure projects. BIM models aid in clash detection, coordination, and facility management. For instance, during the expansion of Hong Kong International Airport (HKIA) for third runway projects, BIM facilitated precise coordination of terminal facilities, baggage handling systems (BHS), automatic people mover (APM), and MEP services. This streamlined construction and minimized disruptions.

A4. Use a case study, and develop the LOD responsibility matrix for LOD-G, LOD-I and DOC.

To develop the LOD responsibility matric, the Definition of LOD shall be specified. LOD requirements shall be cumulative. For instance, a LOD 500 model element shall also fulfil all the requirements of LOD 400 and below. 

For LOD 400, the model shall reflect the contractor's as-built status. The model element is graphically represented within the model as an actual system, object or assembly in terms of size, shape, location, quantity, and orientation, which are typically required during the construction phase and can be measured directly from the model without referring to non-modelled information such as notes or dimension call-outs. Other parametric information such as detailing, fabrication, assembly, and installation information shall also be included. Any finished materials shall be accurately modelled based on specific types.

For LOD 500, the model element shall include all required graphic and non-graphic information of LOD400. The model shall reflect the as-built status with on-site verification. The model element is a field-verified representation in terms of size, shape, location, quantity, and orientation. Non-graphic information shall also be attached to the model element.

For building services, such as Electrical System, the following table shows 3 nos. of sub-systems under the Electrical System for LOD matrix and LOD definition guideline.

A5. What BIM-related software do you use in a project (to realize the above or more applications in the AEC industry?) and state their characteristic, strengths, limitation versions, file formats and interoperability.

The BIM software commonly used in my project is mainly Navisworks Manage, which is usually used for coordination, visualization and project model review, comment and approval.

Characteristics of Navisworks Manage:

1. Holistic Coordination: Navisworks facilitates coordination by combining models from various disciplines (architecture, structure, MEP, civil, etc.).
2. 3D Visualization: It provides visualized and unified design and construction data within a single federated model.
3. Project Review and Comment: Teams can review the model easily, and add and revise the comments on the model for the contractor’s further update and revision.
4. 4D / 5D Simulation: Animate and interact with model objects for simulation, create schedules directly from project models, and import schedules and cost items from external project management applications. 

Strengths of Navisworks Manage:

1. Clash Detection: Identify and resolve clash and interference problems before construction begins, saving time on site and in rework.
2. Collaboration: Keep project teams collaborating and connected effectively using shared models
3. Project Simulation: Navisworks allows for simulating construction processes.

Limitations of Navisworks Manage:

1. Resource-Intensive: Handling large models may require relatively large computing resources.
2. Not a Design Tool: Unlike Revit, Navisworks is not primarily a design tool. (but a good review and comment tool)

Supported Versions of Navisworks Manage (commonly used):

• Navisworks versions include 2024 to 2020, and earlier.
• AutoCAD Drawing - .dwg, .dxf (up to AutoCAD 2018)
• MicroStation (SE, J, V8, & XM) - .dgn, .prp, prw (up to v7, & v8)
• Revit - .rvt (up to 2011–2022)
• 3D Studio Max - .3ds, .prj (up to 3ds Max 2018)
• …

Supported File Formats of Navisworks Manage:

• Navisworks has its own native file formats: .nwd, .nwf, and .nwc.

Interoperability s of Navisworks Manage:

• Navisworks can combine 3D models from various sources into a complete and coherent project model. Whether the models originate from Revit, or other Autodesk BIM software.