Cad modeling technology for building engineering based on extended diagram and polymorphic model

This paper analyzes and researches the CAD modeling technology of construction engineering through extended diagrams as well as polymorphic models. This paper takes the CAD model of the process plant as the main research object and researches the retrieval and intelligent design technology of the 3D engineering model by combining it with the actual engineering application requirements. The paper firstly proposed the unified representation method and similarity evaluation principle of engineering CAD model; then studied the global and local similarity measurement algorithm of 3D model of process plant, and the similarity measurement algorithm of 2D engineering drawing and 3D model respectively; finally realized the intelligent prediction in process plant design by mining the implicit design rules in the model. The complexity of process plant CAD models is manifested in the huge number of components and complex topological relationships. Because different process plant models have different types and numbers of topological relationships, this paper firstly proposes a relationship tree model to count the distribution of topological relationships of the models; then the distribution of topological relationships is used as features of the models, and the similarity between the features is calculated to measure the similarity of the corresponding 3D models. © 2022 CAD Solutions, LLC.