Structural Modelling for Quantity Estimation within an Infrastructure Project

The purpose of the work done on this thesis was the 3D modelling in Autodesk Revit followed by the process of experimenting and analyzing the different ways of quantity takeoff within an infrastructure project. The quantity takeoff refers to the list and quantity of the materials needed to complete a project. Construction takeoffs are an essential part of the planning phase since the material quantity cost is regarded as a significant portion of the total project cost. It needs to be done right to get accurate quantities. The aim of this project consists not only on the final results obtained from the procedure of the material takeoff, but also on finding ways to speed up this process. Complexity of todays projects requires fast, simple, and automatic ways of calculating and organizing the quantities for the final outcome. The project starts with the modelling done in Autodesk Revit of two civil works (construction shaft and station) of an infrastructure project (specifically of a metro line). The 3D design of the structures is based on the available AutoCAD documents. These files contain the 2D drawings of the structure, which may be section, plan, or details views. Using AutoCAD drawings, elements are created separately to be then joined in a complete 3D model. The work proceeds with the analysis of the different ways to obtain and manage the quantities from Autodesk Revit into Microsoft Excel. The goal is to find ways to speed up and ease the process of exportation and importation of the data between Revit and Excel. The methods used during this project development included the direct exportation of the data, usage of add-ins and finally, Dynamo. Direct exportation of schedules from Autodesk Revit is the fastest and simplest way. Usage of add-ins provides a wider option of data managements between Autodesk Revit and Microsoft Excel, however limited, compared to the last method used which was Dynamo. Dynamo gives the flexibility that other methods do not have it. The possibility to create the scripts according to one’s needs is the great feature that Dynamo possesses. Using the nodes, one can create a script depending on its necessity on a specific project, without having to rely on automatic commands of plug-ins. The Dynamo scripts can also be saved and used for future projects. The final part of this project concerns the topic of georeferencing between Civil 3D and Autodesk Revit. A new plug-in has been tested so that the coordinate system between Civil 3D and Autodesk Revit match. Experimenting with different software and tools and exchanging data in an efficient manner is crucial in the construction industry. Communication and information sharing are important not only for the tools but also for the teams working in a project. This is where the idea and concepts of BIM (Building Information Modelling) are becoming more and more necessary and fundamental to be included in every kind of project. The quantity takeoff before the start of the construction is one of the strong points of BIM. The right estimation of the cost in the planning phase reduces the risk of litigation and claims during the construction. However, what really determines the success of a project is communication and collaboration between the project teams. People make the technologies work and not the other way round. Teamwork, cooperation, and communication are what is needed to have successful and satisfying results in the construction industry.