Analysis of Natural Characteristics of Pipe Conveying Fluid in Liquefaction Soil

摘要

The underground pipeline in liquefaction soil was simplified as a simple beam with the action of elastic force of liquefied soil along it, which its ends were supported by linear elastic springs and restrained by torque springs of non-liquefied soil. Considering the interaction of buried pipeline-soil and fluid-structures, the mode superposition method was used to analyze its natural characteristics. The simulating results showed that the natural frequency of buried pipeline while soil liquefied under the action of seismic loading is proportional conversely to pipe span, fluid flow rate and pressure inside pipeline, axial compression force of pipe section and the density of fluid, but is proportional to elastic constraint coefficient of the end non-liquefied soil, relative elastic coefficient of liquefaction soil and axial tensile force.