Research On Time-spatial Conflict Detection And Automatic Avoidance Algorithm Of Underground Pipeline In Urban Tunnel Construction

As the carrier of multi-level data information,Building Information Model is of great significance for the coordination and optimization of traffic infrastructure in various stages of design,construction,operation and maintenance.Engineering experience shows that the urban tunnel construction project inevitably involves the new construction and relocation of underground pipelines,which exposes the collision conflict in the design and construction stage.The intuitive visualization characteristics of BIM technology can play a role in collision coordination,thereby reducing the probability of design errors encountered by construction personnel in construction and reducing the time cost of construction and installation.The existing research on BIM collision behavior has insufficient consideration on the identification of irrelevant collisions and feature collisions generated in the design stage.The definition of collision detection rules in BIM collision detection software has not been unified.In addition,3D collision detection with BIM technology has become a hot research content of construction informatization.However,in the late stage of collision detection,the degree of automation of how to coordinate the detected collision is too low,and there is still a blank in the research on rapid coordination solutions for hot spots in large-scale collision areas.This paper focuses on the spatial-temporal conflicts faced by infrastructure structures such as underground pipelines in urban tunnel construction,and conducts experimental verification based on the proposed method in the actual underground pipeline relocation project.First of all,from the perspective of pipeline relocation nature,system engineering nature and relocation construction process,it directly refers to the relocation needs of underground pipelines in existing urban tunnel construction projects.The basic theory of collision detection of underground pipeline BIM model is proposed from the perspective of collision causes and collision types.Combined with the data flow mode in the process of BIM collision detection,the workflow of coordination and optimization mechanism based on collision detection is formulated,which provides an organizational and coordinated application scheme for the smooth development of underground pipeline collision detection in urban tunnel construction projects.Secondly,according to the characteristics of underground pipeline BIM model,pipeline collision detection and filtering based on BIM spatial component recognition are studied.The detection rule base is established from the perspective of collision causes,and the rule contribution rate is introduced to quantify the effectiveness evaluation of the specified rules.The BIM collision detection and filtering analysis based on the rule base are realized.Then,a spatial-temporal dynamic conflict analysis method for underground integrated pipelines based on BIM-4D schedule deduction is proposed.The BIM-4D construction schedule simulation software is used to connect the three-dimensional model and the construction schedule to simulate the progress process of the phased relocation of the underground pipeline during the whole construction period,so as to identify the potential temporal and spatial conflicts in the existing design scheme.It is proved that the space conflict of some models can be solved by reasonable schedule planning during the pipeline relocation construction,and the BIM-4D space-time conflict detection method is of great significance in the construction phase of pipeline relocation project.Finally,according to the results of space-time conflict,the research is carried out from two dimensions of space coordination and time coordination.Part of the conflict caused by unreasonable progress planning is further resolved in time.The spatial range and target coordination line type to be coordinated are determined in space,the automatic clearance and reconstruction scheme based on collision neighborhood extraction is established,and the automatic path planning algorithm for pipeline collision avoidance is designed.Finally,the coordinate set of key points of the pipeline after coordination is obtained,and the design feedback after conflict avoidance is realized.It is convenient for designers to remove and reconstruct the local model of the collision area in BIM modeling software,and realize the identification,avoidance and redesign of the temporal and spatial conflicts of underground pipelines.