The Experimental Research About Mechanical Property Of City Occupying Gas Pipeline

Gas pipeline is an important part of urban lifeline. When gas pipeline suffers exte rnal load, the safety of pipeline performance mainly embodies in the mechanical properties of the pipeline itself. According to data, the mainly damages of gas pipeline are: cross-section compression, bending failure, shear failure. Therefore, there is a gr eat significance on the study about mechanical behavior of gas pipeline.According to the status about mechanical properties of gas pipeline at domestic and overseas, the paper conducts compression, bending and shear experiments on the seamless steel tubes frequently used for gas pipeline and analyze the mechanical prop erties and all kinds of limit state of seamless steel tubes under external load. The main study contents are as follows:1.Summarize the current research status of gas pipeline at domestic and overseas, analyze the external load types and the causes when gas pipeline damages.2.Conduct cross-section compression performance research about five kinds of pipe diameter such as DN57, DN89, DN108, DN159 and DN219, test data of their be aring capacity under different condition, strain, displacement, and get the conclusion t hat radius-thickness ratio of pipe is the main factor that determine bearing capacity of pipe cross-section. And the bigger radius-thickness ratio is, the cross-section bearing c apactiy is smaller.3.Conduct longitudinal bending performance research about five kinds of pipe diameter such as DN57, DN89, DN108, DN159 and DN219,when the pipe in longitudinal bending process, at the beginning of the load have undergone a linear elastic deformation stage, strain and displacement of the pipeline has the very good contact, under the same load, the larger the diameter, the smaller each measuring point displacement and strain. Pipe deformation is the characteristics of stressed deformation of beam.4.Conduct pipeline in shear ABAQUS simulation about five kinds of pipe diameter such as DN57, DN89, DN108, DN159 and DN219, the results show that,under the effect of shear, the pipeline when well short of yield strength, buckling occurs pipe damage, therefore, should pay special attention to pipeline under the stress of shearing action.