基于BIM技术的地铁基坑工程施工仿真模拟方法

Construction simulation method of metro foundation pit based on BIM technology

如何在地铁基坑施工过程中充分利用复杂地质和工程结构的多源异构信息,实现施工数字化建造是地铁工程建设中的一个难题。通过提出建筑信息模型(BIM)定制化思路,有效集成工程结构体和岩土体模型,建立岩土体开挖与结构体施作同步进行的基坑施工仿真模拟方法,来解决这一难题。采用工业基础类(IFC)标准,分别针对地质体和工程结构进行扩展和定义,构建基于IFC标准的基坑工程基础数据体系。在Autodesk软件平台上,研发基坑结构构件库和参数化构件建模技术,创建自定义的基坑结构建模插件。构建基于钻孔数据的三维地质建模方法,建立面向施工过程的地质模型动态剖切方法,将地质模型离散划分不同开挖阶段的三维地质块体,形成基坑分阶段施工三维地质模型。在此基础上,研究地质体与结构体融合的拓扑重构算法,构建基坑多阶段开挖一体化集成BIM模型,动态加载施工进度信息,形成基于BIM技术的地铁基坑工程施工仿真模型和模拟方法。最后,通过工程实例展示所提出的仿真模拟方法的可行性与有效性。

How to make full use of the multi-source heterogeneous information of complex geology and engineering structure in the process of metro foundation pit construction to realize the construction digital fabrication is a difficult problem in metro engineering construction.In this paper,an idea of building information modeling(BIM)customization is proposed to solve this problem by effectively integrating engineering structure model and geological model,and establishing the foundation pit construction simulation method of dynamic coupling between earthwork excavation and retaining structure construction.Using industry foundation classes(IFC)standard,the geological body and engineering structure are extended and defined respectively,and the data system of foundation pit engineering based on IFC standard is constructed.Based on the Autodesk software platform,the foundation pit structure component library and parametric component modeling technology are developed to create a plug-in foundation pit structure modeling module.The three-dimensional(3D)geological modeling method based on borehole data is established,and a dynamic cutting method of geological model for the construction process simulation is established.The geological model is divided into 3D blocks at different excavation stages,and the 3D multi-phase geological model is formed.On this basis,the topology is reconstructed and the geological body and retaining structure are integrated;the multi-stage excavation BIM model is thus constructed.By dynamically loading construction schedule and time information on the integrated multi-stage model,the construction simulation method of metro foundation pit engineering based on BIM technology is then developed.Finally,the feasibility and effectiveness of the proposed simulation method are demonstrated through an engineering example.