Research On Characteristics Of Damage Development About Buried Water Supply Pipeline Under Seismic Action

Underground pipelines as an integral part of urban lifeline engineering are widely distributed.Because the pipeline is buried underground for a long time during the using process,it is easily affected by varying degrees of damage caused by the complex surrounding environment,which means that the safety of this system is buried with serious hidden dangers.The occurrence of disasters such as earthquakes on underground pipeline with defects will seriously threaten urban security and cause huge losses.Although domestic and foreign scholars have matured the research on the destruction of buried pipeline under seismic action and obtained a large number of calculation models and theoretical results,it is still necessary to conduct further research for the characteristics of damage development on buried pipeline with defects and the damage prevention of buried pipeline under seismic action.The purpose of this paper is to study the characteristics of damage development on buried water supply pipeline with defects under seismic action,to provide a technical support for improving the seismic design theory of buried water supply pipeline and rationally formulating maintenance regulations for buried water supply pipeline.Based on pipe-soil interaction theory,fluid-solid coupling theory and soil-pipe-fluid coupling model,this paper used ADINA software to analyze the effective stress of buried pipe with corrosion defects and displacement of pipe socket interface under seismic action.The main research contents of this paper include:(1)Finite element calculation models of buried pipe with corrosion defects and finite element calculation models of buried pipe with socket interface were established based on the pipe-soil interaction theory and fluid-solid coupling theory.(2)Study the influence about the length of the annular corrosion defects,the depth of the corrosion defects,the elastic modulus of the soil around the pipe,and the flow velocity to the effective stress of the buried pipe with corrosion defects by ADNIA software.(3)The effective stress characteristics of buried water supply pipeline with corrosion defects under seismic action was investigated based on the comparative analysis of the calculation results between pipe-soil model and soil-pipe-fluid coupling model.(4)Study the influence of aftershocks on the socket interface of buried water supply pipeline with ADINA software,and establish the connection between the number of aftershocks and the axial displacement of the buried pipe socket interface.(5)Study the influence of different levels of intensity aftershock on the damage development of the socket interface with injuries by changing the magnitude of the aftershock intensity on the buried pipeline with socket interface.