No longer is 3D modeling a rare occurrence in the building design process. Building Information Modeling (BIM) is a widely accepted practice growing steadily more powerful with advances in computing power, especially with the latest trends in mobile and cloud-based computing. BIM is a key tool for maximizing efficiency and performance in buildings and other infrastructure.
But the built environment is more than it’s individual parts. It is the integrated whole, the impact each element has on its surrounding environment – now and going forward – that determine how livable and sustainable our human-built environment is.
Ideally, then, the concept of BIM is implemented best when it is applied to the greater whole of the built environment instead of just the individual parts.
Seattle: A case study for 3D model integration
Integrating Seattle’s urban center into a cohesive 3D model began about six years ago when the local office of venerable infrastructure design and engineering firm Parsons Brinkerhoff had several major projects on tap ranging from mixed-used condo development to retrofitting the Alaskan Way Viaduct and Seawall. Representing clients both public and private, these various projects each presented their own particular challenges and objectives. From this variety, however, a pattern started to emerge:
“We realized our clients all really wanted the same thing,” say Andrea Barry, Business Development/Program Manager for Project Visualization for Parson Brinkerhoff (PB). They wanted to “see their project in context” with the surrounding environment, understand traffic patterns and access run different “what if” scenarios.
As PB worked building out the immediate models for individual clients, “project overlap” began “knitting themselves together organically,” says Barry. The larger implications and applications of digital modeling – the “bigger picture” – started to fall into place for PB, leading to a “more structured and integrated approach” toward the modeling process.
From the constituent client modeling projects a fully integrated and adaptable 3-D city model of downtown Seattle began to develop. Using a combination of datasets including GIS, laser data and even photography of exterior structures, models of the core downtown Seattle area can be adapted – or “aggregated” - for specific purposes. Like the city it represents, the model is an ongoing work in progress, that now expands from the urban core out to the University of Washington campus and into the city of Bellevue.
Taking it to the streets: Leveraging 3D visualization to the task at hand
Aggregation is a key advantage with this integrated approach to sustainable urban development modeling; the ability to adapt the model based on a variety of datasets targeted to the specific need, location and project. From below ground to street level and aerial view impacts, the modeling process enables qualitative and quantitative assessment of light and shadow, zoning impact, fluid dynamics, traffic simulation, sewer, water, gas and electrical networks.
The impacts of an urban development project are unique from those of a highway retrofit. Both can incorporate models built on datasets targeted to specific “what-if” scenarios that inform all stakeholders, design decisions and policy development. The Seattle Housing Authority’s Yesler Terrace project, for example, leverages the existing 3-D Seattle city model for planning, design and photo–realistic visualization for a new mixed–income and multi-use community to replace aging public housing.
Using the model, what could be conflicting interests in an urban development project like Yesler Terrace can find common ground. Able to see and understand the consequences of decisions before a single brick is laid, a healthier, more sustainable and economically viable downtown community is possible when it is first fully visualized early in the design and planning process.
The ongoing process of growing and developing the Seattle city model stimulates ever more ideas on how to use it, says Jay Mezher, manager of Virtual Design and Construction for Parsons Brinkerhoff (PB). The adaptability of the model comes from the diversity of data sources feeding a variety tools to manipulate and shape the city model.
To that end PB works in close partnership with Autodesk, a driving force in helping build the sustainable city, using many of their modeling and design tools including AutoCAD, Revit, and Civil3D to manage the vast amount of data available. Model aggregation (visualization) is done using three different software packages, Mezher explains - 3D Studio Max for high-end simulation and visualization, Infrastructure Modeler for reading the massive GIS dataset component of the model, and finally Navisworks to bring elements together on a timeline or fixed schedule.
In a nutshell, says Mezher, the Seattle City Model is a “dataset housed in multiple software applications and later aggregated in different applications for different purposes.”
The process has proved successful. The Seattle City Model is the prototype for developing an integrated and flexible process for 3D city modeling and visualization. Taking what they’ve learned in Seattle, PB is working with other cities, including New York, San Francisco, Denver, Los Angeles and Doha, to further develop and refine the 3D city modeling concept.
Redefining the role of design
What PB is doing,” says Terry Bennett, industry manager of Autodesk’s Infrastructure Group, “…is really helping to redefine the role planning, design and construction. What you’re really starting to see with Jay and his team is the ability to define high–resolution infrastructure models from various sources into one view and then being able to look at complex simulations that not only give an idea of what the physical infrastructure is going to look like but also how it can perform going forward. And that’s pretty much counterintuitive to the traditional way of approaching projects, how they’re going to be constructed or how they will perform.
Visualizing the sustainable city
As we’ve discussed in previous posts, the city has become the prominent driver of change in our urbanized global society. The city is where people live and carry out their lives and it is most often at the “street level” that real change happens.
As traditional BIM has done for individual buildings, comprehensive 3D city modeling can now do for the larger urban landscape. Affecting positive change, testing new ideas and making the business case for sustainable development depends on how well we can visualize the future consequences of decisions we make today. We have the tools, we need the vision to use them to make our future world a place where all might not only survive, but thrive. As amazing as 3D modeling technology is, it is the human application of tools that marks human progress. Seattle is a good place to start.
Image credit: Parsons-Brinkerhoff