Research On Key Technology Of The Construction Of Large Split Subway Station Based On BIM

With the rapid development of urban construction and the rapid increase of urban population density in China,the problem of urban traffic congestion is becoming increasingly serious.Rational development and utilization of underground space resources for urban rail transit construction has become an effective way to solve this problem.The construction of subway station is the key and difficult point of subway project.With the development of foundation pit project towards “deeper” and “wider”,the scale and difficulty of construction also increase greatly.Therefore,it is of great significance to study deeply the influence law of deep foundation pit construction on the foundation pit enclosure system,surrounding soil and adjacent buildings,and determine the key technology of efficient and advanced subway station construction to ensure the safe and smooth development of subway station engineering.Based on Haping road subway station project on Harbin metro line 3,for by both the underpasses completely separated super deep and wide “split” subway station deep foundation pit and accessory works,using the research method of the numerical simulation,making use of BIM technology to determine the best construction scheme and key technologies on the basis of analyzing and studying the influence law of deep foundation pit construction on the enclosure structure and the underpass bridge.And information management ways are applied on the construction process of subway station project.The main research contents and conclusions of this paper are as follows:(1)Combined with the engineering geological conditions and construction risk source,for the deep foundation pit project on the north and south sides of Haping road station,3D refinement numerical model is established by using Midas GTS NX software.And the effects of deep foundation pit construction on the horizontal deformation of the enclosure structure,the subsidence deformation of the surrounding surface,the horizontal deformation and the vertical deformation of the underpass bridge structure are analyzed.After the completion of foundation pit excavation,the maximum surface settlement and the maximum vertical deformation of the underpass bridge reached 27.30 mm and 11.29 mm respectively,and the vertical settlement of the underpass bridge exceeded the warning value allowed by the criterion.(2)By adopting the engineering underpinning technology,a set of systematic and perfect reinforcing and reforming technical scheme of the underpass bridge is formulated,and the finite element model of the underpass bridge after renovation is established for analysis and research.The maximum vertical deformation of the reformed underpass bridge structure due to the foundation pit excavation is only 8.28 mm,which meets the engineering safety standards.At the same time,the 3D numerical model of the station transfer channel project is established,and the deformation characteristics of the underpass bridge before and after renovation are compared,which further verifies the correctness of the underpinning technology of the underpass bridge.(3)On the basis of determining the construction technical scheme by using the numerical simulation software,BIM technology is introduced to jointly deepen the design of the optimal key technology construction process.This paper analyzes and studies the specific application of BIM technology in the design preparation stage and construction stage of Haping road station project,and constructs a set of practical and effective refined information management scheme for subway station construction,so as to provide reference for the technical optimization and management of similar subway station projects in the future.