The longitudinal response of prestressed cylinder concrete pipe with bell-spigot joints subjected to normal fault

Buried pipelines inevitably pass through complicated geological areas because of their wide coverage. A three-dimensional numerical model subjected to normal fault considering the geometrical and mechanical properties of the bell-spigot joint in Prestressed Concrete Cylinder Pipe (PCCP) is proposed to analyze the effects of location, displacement, and dip angle of fault on the rotation angle and axial translation of bell-spigot joints as well as the effects on the deformation of pipe bodies. At a dip angle of 90 degrees, the maximum joint rotation angle and pipe deformation are larger when the relative location of fault and joints is under the odd configuration than under the even configuration. The kinematic characteristics of joints and the mechanical characteristics of pipe bodies on the moving side are opposite to those on the stationary side. The amount of offset has a significant impact on the longitudinal response of the pipeline. The rotation angle and axial translation of the joints on both sides of the fault increase with increasing fault displacement. When the offset reaches 270 mm, the joint rotation angle is 1.05 degrees, which exceeds the specification limit of 1 degrees. On the basis of numerical results, the simplified estimate of the maximum rotation angle is improved, and the error is reduced to 3%. With the increase of fault dip angle, the affected area gradually moves left to the fixed part. When the dip angle is 75 degrees-90 degrees, the pipeline longitudinal response is large, which is unfavorable to the pipeline safety.