Closure to “Areas of Application for 3D and 4D Models on Construction Projects” by Timo Hartmann, Ju Gao, and Martin Fischer

Abstract

The authors provide a good categorization framework for application areas for 3D and 4D models in construction practices. It will be helpful for the practitioners in finding the most beneficial applications of 3D and 4D models on their projects and also for the researchers in identifying the most promising areas of research. The authors have already explored different possible areas of applications and research; however, the objective of this discussion is to make some additional observations about a few issues related to future research areas for 3D and 4D models. The discusser feels that more points may be incorporated in future studies in order to help readers better understand the authors’ observations. Although 3D computer-aided drafting CAD models are strong visualization tools, they consist of points, lines, polygons, and solids with no topology and no link to a database. As mentioned in the paper, there is a major revolution of building information modeling BIM in the CAD world. BIM is a kind of 3D modeling that includes topology and may be linked with a database. It is a full building life cycle management tool from construction to day-to-day operations to ultimate demolition. The authors mentioned that 3D/4D models, as well as BIM, need to be researched to determine their future use in different applications areas. In the discusser’s opinion, it would have been better if the authors had specified that 3D CAD and 4D modeling should be researched for application in 3D topology, or the industry needs the integration of BIM with 4D tools, or researchers should study the application of 4D tools during the project life cycle as mentioned in the paper , or the 3D and 4D modeling capabilities of BIM should be enhanced. The 4D models require application-level integration to fulfill project requirements such as quantity takeoffs, cost estimation, energy simulations, etc. Hence, software from various disciplines is being used to fulfill such requirements. Architects, engineers, builders, owners, and operators face challenges because different information formats are used to represent the graphical and nongraphical information for a project and this data is difficult to consolidate Isikdag et al. 2008 . During the planning process when using 4D models, planners have to repeatedly reorganize, interpret, and combine the information collected from different software. This process is tedious and frequently produces errors. Therefore, lack of interoperability is a major obstacle to effectively combining information from different sources. BIM provides solutions for overcoming the interoperability problems that