Mechanical properties of pipeline

Pipeline dimensions

pipeline

Mechanical properties of soil

Soil

Pipeline dimensions

soil- pipeline boundary condition

Boundary condition:
For this study, assumed infinite length for buried pipeline. It is acceptable to consider roller
as the boundary of the ends of pipeline because the buried pipeline may be moved with soil
relatively.
Additionally, the bottom surface of 3D-FE soil model is proposed to be completely fixed This
is because the bottom boundary is selected at the known location of a bedrock surface.

soil- pipeline element

Displacement of pipeline

There are two type stresses on pipe: inner stress and outer stress. Inner stress is more than
outer stress because of water pressure, so for this study maximum von misses’ stress has
considered.

For compression von misses stress in pipe line, defined four paths in up, down, right and left
corner of pipeline like pervious section.
Von misses stress of these paths compared in below figures for defined paths.

von misses stress for depth 2 m

von misses stress for depth 4 m

It’s obvious from these figures von misses stress in the bottom of pipeline more than upper of pipeline. Von misses’ stress for bottom path of pipelines in depth of 2 m from ground surface is 34 MPa and for the upper path is 20 MPa also for bottom path of pipelines in depth of 4 m from ground surface is 74 MPa and for the upper path is 35 Mpa.