Application Of BIM In Design Optimization Of Low-tower Cable-stayed Bridge In Karst Area And Hole Formation Of Pile Foundation

In recent years,with the strong support of the state,the infrastructure construction industry has developed rapidly.As an important part of infrastructure construction,bridge engineering conforms to the trend and needs of the times,and continues to develop in the direction of large spans.This will put forward higher requirements on the bridge structure and directly lead to the refinement and complexity of the components.Bring huge challenges to design and construction.At this time,relying only on traditional two-dimensional CAD design,it is easy to form a phenomenon of information isolation,and it is difficult to find conflicts in the design,and these problems are often found only in the construction stage,and then repaired.This process of recycling will inevitably cause waste of resources.Increase construction costs.The emergence of BIM(Build Information Model)technology is gradually changing this status quo.The technology can integrate all the information of the entire life cycle of the project in the model,which fundamentally avoids waste of resources,and has the characteristics of threedimensional visualization and collaborative management,which can effectively solve the problems existing in the design and construction of bridge engineering at this stage.Based on the Peisen Liujiang Bridge Project,this paper studies and explores the application of BIM technology in bridge design and pile foundation construction.Mainly carry out research work on the following aspects:(1)On the basis of understanding the basic concepts and theories of BIM,analyze and summarize the application of BIM technology at home and abroad,showing that the characteristics and advantages of BIM technology can provide new ideas for solving problems in bridge design and pile foundation construction and direction.(2)The three current mainstream BIM software platforms,Autodesk,Bentley and Dassault,were compared and analyzed.According to the respective functional characteristics and applicable fields of the software,the Bentley platform was finally selected as the main solution for this project.(3)In the bridge design stage,research the rapid modeling method based on BIM technology,use Bentley platform Microstation and Open Roads Designer software,combined with parameterization,template library and XML language for rapid modeling,complete the full bridge BIM model The establishment of,summed up a set of modeling procedures suitable for the standardized design of bridge engineering,and solved the problem of low efficiency in traditional bridge design.At the same time,through the three-dimensional collision inspection of various professional models,the design can be further optimized,the time spent on review is reduced,and the quality problems existing in traditional bridge design can be solved.(4)The application research of the secondary development of Microstation and Open Roads Designer was carried out,and the coordinate marking tool and the route report reading tool were created to further improve the functionality of the BIM software in the actual project.(5)In the stage of pile foundation construction,compare and analyze the pros and cons of EVS,Itasc CAD and Lizheng 3D geological modeling software,and finally choose EVS program to conduct 3D geological modeling research for this project.At the same time,in order to solve the problem that the EVS program can not model the caves in the karst area by using the stratigraphic modeling method alone,and the lithology modeling method cannot clearly reflect the defects of the interface relationship between the layers,the advantages of the two are combined.The stratum-lithology hybrid modeling method is compared and analyzed with the original lithology modeling method.Cross-validation shows that the theoretical accuracy of the hybrid model is higher.Finally,import the model into the Microstation to measure the inclination angle of the bedrock surface,realize the interactive use of multi-platform models,make more accurate geological predictions,and provide a basis for formulating pile foundation construction plans.