112 / 116
110
M
ay
2010
www.read-tpt.com›
A
rticle
Conclusions
Important results of this paper include:
1. Buckling pressure of pipeline is increased with a decrease of
ring spacing.
2. Buckling strength of pipeline is related to the number of waves
made-up on specimens.
3. Thickness of rings has no great effect on buckling pressure
against value of used steel in specimens.
4. Using of ring stiffeners has economical benefits over same
weight specimens without rings.
5. Geometric properties of specimens such as length or rings
spacing or diameter of specimens has considerable effects on
buckling behaviour of specimens.
6. There is good corresponding data between experimental and
FEM results according to comparison of buckling pressure and
circumferential modes of specimens.
References
[1]
BS 8010, 1993, Code of practice for pipelines - part 3 pipelines subsea: Design,
Construction and Installation, British Standards Institution, UK.
[2]
API RP1111, 1999, Design, Construction, Operation, and Mainrenance of
Offshore Hydrocarbon Pipelines (Limit state design), American Petroleum Institute,
Washington, DC.
[3]
ABS, 2005, Guide for building and classing subsea pipeline systems and risers,
American Bureau of Shipping, Houston.
[4]
DNV Submarine pipelines system, 2000, OS-F101, Det Norske Veritas, Norway.
[5]
Mesloh, R. Johns, T. G., and Sorenson, J. E. 1976, "The propagation buckle."
BOSS' 76, Vol. 1, pp.787-797.
[6]
Kyriakides, S., & Babcock, C. D., 1981, "Experimental determination of the
propagation pressure of circular pipes" ASME Journal of Pressure Vessel
technology, Vol. 103, pp. 328-336.
[7]
Kamalarasa, S. and Calladine, CR. 1988, "Buckle propagation in submarine
pipelines." International Journal of Mechanical Science, Vol. 30, No.3. 4, pp 0217-
228.
[8]
Murray, D. W., & Zhilong Zhou., 1995, "Analysis of potbuckling behaviour of line
pipe subjected to combine loads" International Journal of Solids Structures, Vol.
32, No. 20, pp. 3015-3036.
[9]
Pasqualino, I. P., & Estefen, S. F., 2001, "A nonlinear analysis of the buckle
propagation problem in deepwater pipelines" International Journal of Solids and
Structures, Vol. 38, pp. 8481-8502.
[10]
Netto, T. A., & Kyriakides, S., 2000, "Dynamic performance of integral buckle
arrestors for offshore pipelines. Part I Experiments" International journal of
Science, Vol. 42, No. 7, pp. 1045-1043.
[11]
Kyriakides, S. & Netto, T. A., 2000, "On the dynamics of propagating buckle in
pipelines," International Journal of Solids and Structures, Vol. 3, pp. 6843-6867.
Figure 17
:
Three wave mode of model A4 in FEM study
Figure 19
:
Three wave mode of model A0
in FEM study
Specimen label
Maximum experimental
mode number
FEM mode number
A0
2
2
A4
3
3
A7
3
4
A13
5
5
Table 5
:
Comparison of mode number between experimental and FEM studies
Figure 20
:
Comparison of experimental and FEM studies with batdorf parameters
Figure 18
:
Three wave mode of
specimen A0 in experimental study
Comparison with batdorf parameters
Figure 20 shows experimental and FEM comparison with batdorf
parameters. This curve indicates that FEM and experimental
results correspond well together. But there are few differences
between these results with batdorf parameters. This is because
specimens were considered in ideal condition such as long length
or sections without imperfections and too elastic a behaviour
was considered for them. In this graph X and Y direction
were considered,
and
respectively.
Which
.
H Showkati – Civil Eng. Department, Urmia University, Iran
R Shahandeh – Civil Eng. Department, Sama organization
(affiliated with Islamic Azad university), Khoy branch, Khoy, Iran