基于IFC拓展模型的邻近施工对既有地铁隧道变形影响研究

Research on the impact of nearby construction on existing metro tunnel structural deformation based on extended IFC model

随着土木行业的信息化发展,BIM技术在土木工程中的应用不断拓展。为解决以往邻近施工过程中难以准确反映施工加卸载对既有建(构)筑物影响的问题,文章依托某邻近既有地铁隧道施工的建筑工程,首先在概述IFC模型多种拓展机制并对比其优缺点的基础上,对BIM模型进行IFC属性集工况信息拓展;然后,通过数值模拟方法,进行邻近施工加卸载荷载模拟,并据此建立IFC实体数据与加卸载施工对地铁隧道变形影响值的数学定量关系;最后,基于IFC模型中的几何数据信息及拓展属性信息,提出能够直观展现施工加卸载对既有地铁隧道变形影响的信息化方法,并对其计算出的影响值与实际施工过程中地铁隧道竖向变形值进行相关性分析。研究结果表明,IFC模型属性集拓展方法能够对工况信息进行有效补充;邻近施工加卸载荷载对既有地铁隧道变形的影响规律呈近似指数函数关系;所提方法算出的施工加卸载对既有地铁隧道变形影响值与地铁隧道变形实际监测值具有较高的相关性,能够准确反映施工加卸载对邻近地铁隧道变形的影响情况。

With the development of informatization in civil engineering industry,the application of BIM technology in civil engineering has been expanding.To solve the issue that it is difficult to accurately reflect the impact of construction loading and unloading on existing buildings(structures)in the past adjacent construction process,this article relies on a nearby construction project adjacent to an existing metro tunnel,firstly,it compares diverse IFC extension mechanisms and extends the IFC attribute set's operating condition information within the BIM model.Then,by employing numerical simulations,the loading and unloading effects of nearby construction are modeled,establishing a quantitative relationship between IFC entity data and the deformation values of the metro tunnel caused by construction loading and unloading.Finally,based on the geometric data and the expanded attribute information in the IFC model,an information method that can visually represent the impact of construction loading and unloading on existing metro lines is proposed,and correlation analysis has been conducted between the calculated impact values and the actual vertical deformation values of metro tunnels during the construction process.The research findings show that the IFC model property set extension method can effectively supplement work condition information,and the impact of nearby construction loading and unloading on existing metro structures approximates an exponential function relationship.The correlation analysis proves that the proposed method for visually representing the impact of construction loading and unloading on existing metro structures shows a good correlation with actual monitoring values and could fully reflect the impact of construction loading and unloading on nearby metro line displacements.