Strength analysis of buried curved pipes due to blast explosions
File(s)
Published version
Author(s)
Provatidis, Christopher
Kanarachos, Andreas
Venetsanos, Demetrios
Type
Chapter
Abstract
With the advent of new low-cost and powerful computers and explicit time integration FEM codes, three-dimensional models are now available for the
transient response analysis of buried structures due to blast explosions in their proximity. In the industrial domain, a most interesting issue is to determine the
critical distance between the center of the explosion and the buried structure in order to insure its integrity. In the present paper a systematic study is presented
on the stresses induced to buried pipelines, focussing on their curved parts such as elbows and tees. In more detail, it was examined whether the curved parts of a
pipeline suffer more compared to the straight parts. For the purposes of the present study, the distance from the center of the explosion, the depth from the ground surface and the impulse of the explosion are considered to be fixed. On the contrary, the shape of the pipeline is variable, as well as the relative position of the pipeline with respect to the center of the explosion. The entire analysis was based on a 3D explicit code (LS-DYNA, version 950). The main outcome of the study is that in all cases taken into account, the equivalent von Mises stresses exerted on the curved parts are either smaller or at most equal to those exerted on the straight parts of the structure. The numerical results lead to the conclusion that for fast and safe decision making, the curved parts of a pipeline may be ignored. Nevertheless, a more thorough investigation is required in order to
extend this conclusion to other cases where the radius of curvature is different than the one chosen for the needs of the present study. Finally, the influence of other parameters, such as the impulse characteristics, the soil layer characteristics, the depth, the backfill etc, should also be further examined.
transient response analysis of buried structures due to blast explosions in their proximity. In the industrial domain, a most interesting issue is to determine the
critical distance between the center of the explosion and the buried structure in order to insure its integrity. In the present paper a systematic study is presented
on the stresses induced to buried pipelines, focussing on their curved parts such as elbows and tees. In more detail, it was examined whether the curved parts of a
pipeline suffer more compared to the straight parts. For the purposes of the present study, the distance from the center of the explosion, the depth from the ground surface and the impulse of the explosion are considered to be fixed. On the contrary, the shape of the pipeline is variable, as well as the relative position of the pipeline with respect to the center of the explosion. The entire analysis was based on a 3D explicit code (LS-DYNA, version 950). The main outcome of the study is that in all cases taken into account, the equivalent von Mises stresses exerted on the curved parts are either smaller or at most equal to those exerted on the straight parts of the structure. The numerical results lead to the conclusion that for fast and safe decision making, the curved parts of a pipeline may be ignored. Nevertheless, a more thorough investigation is required in order to
extend this conclusion to other cases where the radius of curvature is different than the one chosen for the needs of the present study. Finally, the influence of other parameters, such as the impulse characteristics, the soil layer characteristics, the depth, the backfill etc, should also be further examined.
Date Issued
2000
Citation
Structures Under Shock and Impact VI, 2000, 48
ISBN
978-1-85312-820-2
Publisher
WIT Press
Journal / Book Title
Structures Under Shock and Impact VI
Structures and Materials
Volume
48
Subjects
Science