Seismic Response Analyse Of Buried Pipe Across The Riverbed

As one of the important lifeline system to transport the energy and water etc.,buried pipeline faces seismic hazard which is the biggest natural disaster for buried pipeline.In this paper,the numerical analysis to seismic response of buried pipeline across the river site is studied.the topographic effects and seismic response of underground pipelines across the river valley are analyzed and simulated based on the ABAQUS software,these results are valuable for aseismic design of the pipeline buried across the river.The main contents are as follows:Firstly,based on the reviewing these researches related to the seismic response of buried pipeline in different site condition,the state of the art of seismic response of buried pipeline is investigated,several key problems in numerical analysis of buried pipeline under earthquake invading are discussed,then the research's plan in this thesis is constructed.Herein,the topographic effect,liquefaction effect to the seismic response of buried pipelines are included.Secondly,the numerical models to simulate the seismic response of soil layers across the river is established in the platform of ABAQUS software.In this model,the topographic and stratum effects of river valley with seismic wave are analyzed,and different parameters,including the frequency of earthquake,valley depth,valley width,mountain height and slope angle,are considered in the analysis.Then,an empirical formula for estimating the acceleration amplification factor is proposed after series of simulation and theory.Thirdly,the ABAQUS is used to establish the numerical model of buried continuous steel pipe built across the river.The seismic response stress of pipeline across the river are analyzed,and the most safe buried depth of pipeline in different site condition is discussed based on analysis of the variation of site condition parameters and pipeline parameters,such as valley width,valley depth,slope angle,pipeline diameter,thickness and pipeline burial depth.Finally,the floating characteristics of pipeline due to seismic wave is analyzed.In soil liquefaction site,the minimum buried depth of the pipeline is calculated to keep its safety,and an empirical formula for estimating floating displacement is given,and the variation of pipeline parameters on pipeline floating response,including pipe diameter,thickness and pipeline buried depth,are systematically studied.