Its All About the Data: BIM to CIM, the Acronyms Demystified

Written by Marco Cecala

Created on Saturday, 05 September 2009 12:30

For some time, the vertical builders have been toying with BIM. Here is the definition. Building Information Modeling (BIM) is the process of generating and managing building data during its life cycle. Typically it uses three-dimensional, real-time, dynamic building modeling software to increase productivity in building design and construction. The process produces the Building Information Model (also abbreviated BIM), which encompasses building geometry, spatial relationships, geographic information, and quantities and properties of building components.

I have heard both good and bad stories surrounding the adoption of BIM as a way to build structures. As with any technology there will be mountains to climb. Not to be outdone, the Civil community is working on adapting CIM, (you can figure it out) to provide the same benefits promised for buildings. A design is changed at one workstation, and the entire team’s electronic documents are updated. Comment and review goes smoother and everything fits. What’s not to like?

In actuality both CIM and BIM have been available to designers for years. Every time a CAD tech makes changes to a project, other members of a team are able to see what the latest and greatest is. What the integration philosophy is spawning is software programs and plugins that notify, track and record the process of proposed changes. This additional layer provides documentation and recording of the process for the all important paperless trail. The disconnect comes when changes and deadlines collide. All too often the last changes of a project are subject to field adjustments and life goes on.

We are a technology business, anytime that we can streamline our work it benefits the contractor and the project as a whole. Things get cheaper, faster, and better. I am not trying to talk poorly of this technology. I am referring to human nature as it is applied to deadlines. As it gets closer to drop dead day things get rushed. For CIM to work properly, all teams need to review the impact of a change and comment on its validity. If a group of last minute changes are proposed and everybody does not get to approve them, the effectiveness of BIM is greatly reduced.

There is no easy answer besides the obvious. Change human nature in regard to deadlines and have the project wrapped up in plenty of time. Not likely but the most logical answer.

To put the details of the process into practice I will outline a small change to a street project. Our city has decided to place a bus stop on a street rehabilitation project. The bus turn out will add a 12 foot lane for 150 feet along the street. There is a curb drain in the street and a small off site retention.

As requested by the city, the engineer draws in the bus stop.

A Shelter and changes to the sidewalk are added.

The agency responsible for right-of-way procurement is contacted. They need to purchase additional land because the retention is now pushed back 20 feet.

The storm drain structures and pipe need to be reworked due to the addition of a new lane.

The city reviews and notes required changes.

The process can begin again based on the depth of the changes.

As contractors we might just make the new bus stop work in the field. The CIM process can get expensive for even the smallest of adjustments; the increase in design cost must be offset by a huge advantage. For CIM to be economically feasible the job needs to be ready to build from the electronic files.