Design of multi-layered building structures using BIM method

Today BIM is an inevitable concept in construction design and while the workflow of consultant designers is mostly influenced to a small extent, new methods require a new kind of communication between them. This research focuses on the workflows of construction designers because their design works have a big impact on many other disciplines. This paper presents an examination about the processing methods of the building structure designers and the use of BIM with a questionnaire survey. In this research, a new way was also introduced to integrate definitions of multi-layered structures (created by construction designers) into the BIM/CAD model itself. The goal was to allow the data in the layer structure documents to be automatically linked to the model, and make it possible for all collaborators to continue working with the data separately. This paper proofs that this automated workflow greatly increases efficiency, accuracy and reduces human errors. ArchiCAD and Excel were used as our development framework: former one to create CAD/BIM models, latter one to handle the database of multi-layered structures. Individual codes were used to identify each unit of the layer structure and link them to the model itself. This way, it is not necessary to manually add the data to the elements, but the material properties can be read automatically into the model and the quantities can be measured. Similar scale, size, and complexity buildings were selected as a test environment where the ordinary and the new method were used in parallel throughout the design process. This provided a good comparison and demonstrated the effectiveness of database-based design. With the new approach, time required for first-round quantification was reduced by 41% and the time of a repeated quantification due to modifications was reduced by 56%, in average.