Experimental and Finite-Element Studies of Buried Pipes Connected by a Bellow Joint under Cyclic Shear Loading

Abstract

In an accompanying paper, pipes that were connected by a bellow joint were examined under cyclic axial loading. The results show that the bellow connection can significantly reduce the axial force and increase the deformation capability of the pipe-joint system. In this work, the pipes connected with a bellow joint were further investigated under cyclic shear loads. The pipe was buried in two steel boxes filled with soil. One box was fixed to the strong floor, and the adjacent box can move in a transverse direction. The ends of the pipe were each fixed to the far surface of the boxes. A transverse cyclic shear displacement was applied to the movable box. Axial elongation along the pipe, shear load, and deformation were recorded by a data logger. The results indicated that most of the deformation of the pipe-joint system was contributed by the joint, so less damage to the pipes was observed. A finite-element (FE) model with and without a bellow joint was then developed to evaluate the effectiveness of the joint. The results of FE analysis and the experiments showed that the pipe with a bellow joint experienced much smaller axial force and had greater deformability compared to the pipe without a bellow joint.