Study On Anti-seismic Performanceof Arch Pipeline

With the rapid development of China's national economic construction after the reform and opening up,the great demand for energy resources has spawned the leap forward development of pipeline engineering.The spanning pipe structure is widely used in the current lifeline engineering.But the study of domestic arch crossing pipeline is less involved in its inherent frequency,vibration characteristics,seismic performance and seismic response characteristics of the dynamic characteristics.Most of them remain in the level of the theoretical discussion and the integrity introduction,but not in-depth analysis of its internal mechanism and characteristics.They face the same problem in the standard design requirements.If a sudden strong earthquake happens,it is likely to cause damage to the pipeline structure and cause heavy losses.So studying the arch suspending pipeline's dynamic characteristics,response,stress and strain distribution characteristics in earthquake is of great significance for avoiding damage in earthquake and providing reference for practical seismic design of arch pipe.This paper determinesthe basic parameters of arch crossing pipeline through the self-vibration frequency of the arch crossing pipeline.The model of large span arch pipeline is established through finite element analysis software.According to the principle of structural dynamics,this paper analyzes and calculates the self-vibration frequency,self-vibration mode and the rules of displacement of arch crossing pipeline in the liquid content of different pipelines,different pipe span,different pipe radian,different pipe caliber,different pipe material,process and so on,providing theoretical reference for seismic response analysis.The paper uses two kinds of seismic waves to stimulate pipelines,and analyzes several special positions of arch crossing pipeline under multiple different span conditions,namely the left and the right support.The characteristic sections of 1/3 span and 2/3 span means that the liquid content is 1/3 span or 2/3 span of the pipeline;it's the response characteristics of full span submerged arch pipe filled with liquid.The paper also analyzes the seismic response of pipelines under different pipe geometry parameters,including pipe span and pipe bore condition.And arch crossing pipeline belongs to the large span structure,which needs to consider the traveling wave effect under uniform excitation and the influence on the seismic response of the arch pipe under the condition ofv=200m/s,v=60m/s.Different conditions of coherence,namely considering or not considering local site effect,the displacement and stress and strain situationof arch crossing pipeline should also be considered.The characteristics of seismic response of arch pipe under these conditions are analyzed.It can provide some data and theoretical reference for seismic design of practical pipeline.Finally,based on the current seismic design method of domestic mainstreamrelated to structural performance,combined with the characteristics of dynamic properties and seismic response of arch pipe describe before,the paper preliminarily discusses the basic seismic performance ofarch crossing pipeline.The situations should be paid attention,some necessary protective measures to avoid the damage of seismic reinforcement and the adverse effects of earthquake may be caused by arch pipe are also discussed.