(Mis)understanding BIM
2015-06-11     浏览:68    评论:0        
导读:At the risk of sounding like a BIM geek I wanted address some of the common misconception(s) that I have come across while servicing (BIM specific) requests from both Consultants and Contractors. Ther
 At the risk of sounding like a BIM geek I wanted address some of the common misconception(s) that I have come across while servicing (BIM specific) requests from both Consultants and Contractors. There seems to be a lot of noise and bandwagon-ism surrounding BIM; the entire industry is talking about it, and yet, the more they talk, the more they sound confused.

We all have come across textbook definitions of BIM yet unlike CAD, which means Computer Aided Design – a term which is virtually indefinable yet everyone inherently knows its meaning purely because of the context in which it is used, BIM seems to have very little or often a confused context. So what is BIM and why is there so much of hype, anxiety & confusion around it??? I don’t claim to be a technical expert and for the sake of people, who like me, are BIM novices, I reckon it would probably be easier to start by defining what BIM is not.

BIM is not 3D

A 3D model is not BIM!!!! Creating a 3D model alone does not give you a Building Information Model solution. Not unlike me, those of you who have worked on CAD would know that you can create a 3-Dimensional model in AutoCAD as well, but that model by no means would qualify as a BIM model. The simple reason to that end is the absence of any added intelligence, which would give you any “data” about the project. In such a non-intelligent 3D model, to understand each element it would be necessary for the person to interpret the element based purely on its geometry – there is simply no intelligence/data other than its geometry. Now consider adding some intelligence to the elements in a 3D model – for e.g. material specification to the doors/windows/walls etc and voila, the 3D model has now become “BIM”  (albeit simply). I do understand that it is a very crude example but I hope it makes its point.

 BIM is not Revit

If there is one thing that most folks in the design and construction industry could agree on, then it would be that Autodesk has got a powerful marketing machine…Since my early years as a graduate training to be an Architect, I’ve heard people talk about making drawings in “CAD” and it was never once asked “what software”? It was always inherently assumed to be AutoCAD. The same trend seems have to engulfed the BIM domain – the terms BIM and Revit have almost become interchangeable. Please be aware that Revit, while being a potent BIM solution, is not the only solution out there; and conversely, you can do a whole lot of 3D modeling on Revit without it being truly/remotely “BIM”.

BIM is not a “single building model”

This is one of the biggest confusions that I have come across regarding the adoption of BIM. A lot of people consider BIM to be a single model from which the stakeholders can extract relevant information in a format they require. In reality it is better to visualize BIM as a series of distinct models - you may have a separate Architectural model, a Structural model and distinct model(s) for each of the Building services (M, E, P, FP). Each model is a distinct entity/databank of information and allows individual access to a package of work. When these distinct model(s) are brought together do we get a true BIM solution; the idea behind a building information model is that of a single consolidated repository/database and not a solitary model. Both graphical documents/drawings and non-graphical documents - specifications, schedules, and other data are included in this repository.

 Building information modeling solutions have three characteristics:

  1. They create and operate on digital databases for collaboration
  2. They manage change throughout those databases so that a change to any part of the database is coordinated in all other parts
  3. They capture and preserve information for reuse by additional industry-specific applications.

BIM is not Project Lifecycle Management

Another interesting assumption that seems to come through when one talks of BIM is that “it can be BIM only and if only everyone on the team from design till FM is involved”. I don’t disapprove of this and to be honest I believe in a perfect world/project BIM would/should provide well-managed data which would flow through the design, construction and operations phases of the project – that said, it is not a perfect world, atleast not yet!!!

In fact I almost always advice my clients to have a myopic vision/expectation of what they eventually want to achieve from BIM on their project(s) – for someone who is starting down the BIM road it is critical they focus/consider only on their internal benefits initially – it could be improving quality of coordinated drawings or improving production schedule, or the combination of both or any number of design processes or objectives. Understand the challenges and figure out a solution around those challenges to reach your defined objectives. only once you have mastered this and developed/tested/refined working procedures for your practice, should you start to consider collaboration with other stake-holders. It’s better to take it one simple step at a time; I’m a strong believer in the principle of the 3M’s – Make, Master & only then would you Matter!!!

So what is BIM?

This is the most concise yet apt description of BIM that I have come across - BIM is the management of project information, both the construction of that data and the iterative process of exchanging it. BIM is the added intelligence to project data that allows anyone to interpret that data correctly, removing the risk of assumptions. BIM is the process by which the right information is made available to the right person at the right time.