Parametrisk modellering av lådbalksbro : Arbetsflöde mellan design och BIM

Sammanfattning

This thesis explores how parametric modelling can be applied to the design of a box girder bridge and how such a model can be integrated into a BIM environment. The background is the growing demand for efficient and flexible digital methods in infrastructure projects, where conventional tools may be either too limited or too resource-intensive for early design stages. The aim of the study was therefore to test a workflow using Rhino and Grasshopper for parametric modelling and to evaluate its usability when transferred into Autodesk Revit. The method combined a literature study with practical modelling experiments. A parametric model of a box girder bridge was created by sweeping a cross-section along an alignment generated from geographic data. The model was then imported into Revit via Rhino.Inside, where its functionality was tested for drawings, measurements, and clash detection. The results show that the sweep method efficiently produced a flexible and adaptable bridge geometry. The workflow in Grasshopper enabled rapid iterations and high transparency, although the absence of real elevation data and the lack of parametric editability in Revit limited its precision and integration. A practical consequence was that piers in Revit clashed with the bridge since they could not be joined to its geometry. The conclusion is that parametric modelling with Grasshopper is a valuable method for conceptual and early design phases. The approach is well suited for integration in Revit and offers a cost-efficient alternative for small and mediumsized consultancies.