Research On Digital Twin Construction Of Hydraulic Engineering Based On BIM+GIS

Promoting smart water conservancy construction is one of the important ways to achieve high-quality development of water conservancy in the new stage.At present,the research on the application of digital twins in the water conservancy industry started late,and the technologies are not yet mature,how to establish a high-precision and multi-fusion data base,synchronous simulation operation with the physical watershed,and virtual and real interaction is the key issue of current research.Therefore,this paper studies the integration of BIM model,oblique photography model and other data into the 3D GIS platform for multi-source data fusion,and constructs a multi-dimensional and multi-scale digital twin scene of water conservancy engineering for application.The main research results of this paper are as follows:(1)Based on BIM technology,the twin model of hydraulic buildings of pumped storage power station was established.The components of key hydraulic buildings in the reservoir area are decomposed,parametric family components are established based on Revit,and highprecision model units containing quantity,geometry,appearance,location and other information are constructed.At the same time,in view of the excessive size of the original BIM model,under the premise of retaining the structure and semantic information of the model file,the edge folding algorithm based on the quadratic error measurement is used to simplify the processing,and at the same time,the constraint factor is introduced to improve the algorithm,retain the boundary characteristics of the model,reduce the degree of deformation,and simplify the triangular mesh,realize the lightweight processing of the BIM model,and provide data support for accessing the digital twin platform.(2)UAV tilt photogrammetry technology is used for multi-view image acquisition,image adjustment processing and intensive matching are carried out based on beam method area network aerial triangulation and multi-view stereo matching algorithm,and 3D point cloud,real scene model and other digital achievements are generated.However,it does not support the direct establishment of digital elevation model DEM.Therefore,DEM production is carried out based on dense matching point cloud data.In view of the complex terrain of hydraulic engineering,the paper adopts the cloth simulation filtering algorithm based on terrain classification and the slope method filtering for comparison experiment,comprehensively selects the algorithm with good classification effect for filtering processing,and conducts data interpolation based on Delaunay triangulation algorithm to generate digital elevation model DEM.Form the basis of hydraulic engineering calculations.(3)In view of the current difficulties in integrating and integrating BIM data,GIS data and other multi-source data,research and analyze the differences in IFC and City GML data standards,convert data formats based on the transformation idea of semantic constraints,connect BIM data to the 3D GIS platform,and carry out model fusion construction.At the same time,based on distributed cache technology,3D tile cache is carried out on BIM models and oblique photography models,pyramid segmentation and compression processing,data access and publishing services are carried out on the Web front-end,and a digital twin map is constructed.Finally,16 influencing factors affecting the application of BIM+GIS data fusion are analyzed,and the fuzzy comprehensive evaluation method based on AHP is used to evaluate the maturity of the maturity,which provides a reference for deeper integration of the two data and applies it to the construction of digital twins of water conservancy projects.This paper mainly focuses on key water conservancy projects,constructs L3 digital base geospatial data such as BIM model,oblique photography model,digital elevation model DEM,etc.,and digitally maps them,which provides a data base for subsequent intelligent simulation and accurate decision-making,and provides reference significance for the construction of digital twin water conservancy engineering data baseplate.