How can 3D modeling in the virtual world help the design and construction of actual buildings? As technology has advanced in recent years, engineers and architects have moved away from drawing and making calculations with paper and pencil to using Computer Aided Modeling, or CAD, to digitally model larger and more complex structures. Mathematical calculations, like those used by Finite Element Analysis and WUFI, can evaluate the projected performance of building materials and systems under real world conditions. These computer programs offer faster, more accurate simulations to better inform the designers, contractors, building owners, and manufacturers.
What is FEA?
Finite Element Analysis (FEA) is an engineering tool used to analyze how physical stresses, including vibrations and heat, will impact a three-dimensional CAD model. While FEA cannot replicate an entire building, it can predict the performance characteristics of systems and individual components, such as a window buck or insulated concrete form, after being exposed to certain pressures. The resulting data can indicate the degree of deformation, strain or fatigue, and heat flux of a product in its environment.
FEA software packages offer the option to do static or transient analyses, which can require heavy computational power to complete. For this reason, it is important that the individual running the program knows how to properly set the boundary conditions of the model and simplify any geometries. There are many ways an analyst can convey the same situation and produce different results. In essence, the FEA tool is only as good as its user.
How FEA Helps the Construction Industry
FEA plays a big role in analyzing building material performance over time in a project-specific situations. For example, it can demonstrate the delamination in adhesives and sealants through cohesive zone modeling and model degradation and fatigue of a product based on experimental data. The results can point out any weak spots in a design to offer recommendations to the architect, contractor or building owner to perhaps optimize cost or ensure structural integrity. The figure below represents a steady-state thermal analysis performed on an insulated concrete form using FEA to visualize the heat transfer through the model. This projection demonstrates how different materials impact the R-value of the wall assembly, which in turn offers insight into the requirements of the building materials needed to meet an owner or designer’s energy-efficiency goals.
FEA also helps to understand how different forces will affect the stress distribution on the model and see how the materials will perform (stretch, deteriorate, buckle, break, etc.) under the applied boundary conditions. This feedback is especially beneficial when working on more exploratory projects or those using less traditional construction technology, as it can aid research and development teams with prototypes and product improvements.
Aside from benefiting new construction prior to breaking ground, FEA can assist existing structures in the case of a building envelope failure. Once a building is completed, it can be difficult to find the source and determine the cause of air infiltration or a structural issue. By interpreting the data in FEA, the user can identify potential contributing factors, such as product selection, application techniques or sequencing, and therefore advise on appropriate repair methods.
Conclusion
Simulation technology, including FEA and WUFI, offers powerful knowledge for manufacturers, contractors, designers, and owners alike. The 3D models and data offer opportunities for more collaborative work amongst the design build community to help build more efficient and long-lasting structures.