Elasto-Plastic Large Strain Collapse Analysis of Pipes

The collapse analysis of pipes is important in a number of industries, and notably in the offshore oil and gas industry. Such simulations are, in general, difficult because the kinematic large displacement/large strain behavior of the pipe and the large strain elasto-plastic material behavior need to be modeled accurately. The analysis must yield reliably accurate results because many important engineering decisions depend on the predicted response.

Since the accuracy of the simulation is very important, the required level of confidence in using a finite element code is best achieved by comparing computed results against experimental data, for some typical pipe structures.

Below we present some results obtained by Tenaris, see reference [1], in laboratory tests and using ADINA. In this case, a pipe stiffened by a ring (an "arrestor" of buckling) was considered. The figures are largely self-explanatory. The movie above shows a typical collapse response as the pressure on the pipe is increased.

First tested sample

First tested sample — finite element mesh

First tested sample — ADINA results compared to experimental results

Second tested sample, with groove

Second tested sample — finite element mesh

Second tested sample — ADINA results compared to experimental results

It is seen that ADINA very accurately predicts the test data. This is an excellent validation of the analysis procedures used in ADINA. More information on the analysis is given in the reference.

Reference

1. R. G. Toscano, L. O. Mantovano, P. M. Amenta, R. F. Charreau, D. H. Johnson, A. P. Assanelli and E. N. Dvorkin, "Collapse arrestors for deepwater pipelines. Cross-over mechanisms", Computers & Structures, Vol. 86, pp. 728-743, 2008.