Numerical Evaluation on Improvement Performance of Waved Connection to Reduce Damage on Buried Gas Pipeline

Abstract

One of the major challenges for the oil and gas industry is to keep buried metal pipes safe from faulting. This paper discusses about a solution to keep buried pipes safe. In this study, after examining the different dimensions of the effect of wave connection on improving the performance of buried metal pipes, by changing the geometric shape of the wave connection such as doubling it, the behavior of the pipe is greatly improved. Waved connections, by their local deformation, create a rotational joint in a limited area so that other parts of the pipe remain intact. In this paper, the behavior of buried pipes due to slip direction fault displacement by modelling with Abacus software version 2017 and selection of 4-node shell element and 8-node shell element have been used for pipe and soil modelling, respectively. In this paper, by comparing to a single waved connection with a double waved connection, the performance of the pipe due to the faulting phenomenon was evaluated. The results show the improvement of the excellent performance of the double joint by reducing the plastic strain values. In addition to increasing the ductility of the pipe, the double connection has been able to reduce the strain values by about 50% compared to the single connection. In general, this paper shows that the use of wave connections can significantly increase the level of safety of buried gas pipelines without increasing the cost.

Explosive Performance Assessment of Buried Steel Pipeline

“…Of course, these relations are also interchangeable. e maximum amount of particle displacement (x) in terms of meters, at a distance of R (meters) from the source of the explosion, entirely or relatively buried, can be estimated from relation (22), where w is the mass of the explosive material in kilograms, c is the seismic wave velocity in meters per second, f c is the coupling coefficient, calculated from Figure 9, and n is the dimensionless reduction coefficient; from Table 3, it is obtained that [19] x w (1/3)…”

“…In this method, the normal contact of two levels with the hard contact method is considered to prevent the surfaces from sinking into each other. Also, the tangential interaction of the two surfaces with a friction coefficient of 0.5 that was suggested by Vasouras and Kolbadi [21,22] is regarded in the analyzes. is number is a suitable value for the interaction of soil with metal structures.…”

Free Span Analysis for Submarine Pipelines

“…Breakdowns resulting from fatigue are a major concern in engineering design [27]. Economic costs of the failure and its prevention are very high, and it is taken into consideration that nearly 80% of these costs include the situations that cyclic loading and fatigue are at least one contributing factor [28]. erefore, the annual cost of material fatigue to the U.S economy is nearly 3% of the GDP and the same percentage is anticipated for other industrial countries.…”

“…On the other word, by increasing the available opportunity for doing the activity without worry about the condition of the fatigue of the pipe, cost of missed opportunity can be decreased and the costs resulting from servicing at other places can be investigated to increase profitability to the employer. Alternatively, it can be to answer this basic question whether it is correct to use a cross model in studies such as in [17,28]. Given the abovementioned graph, it can be said that by considering the bed as a cross, there will be no significant difference in the answers.…”

Experimental Investigation on the Ductility of Concrete Deep Beams Reinforced with Basalt‐Carbon and Basalt‐Steel Wire Hybrid Composite Bars

“…e results of the specimens showed that this process caused nonlinear behavior in these types of hybrid composite bars [23]. Since few tests have been performed on evaluating the performance of hybrid composite bars in concrete elements, in this research project, four specimens of concrete beams reinforced with hybrid composite bars were investigated under statistical four-point flexural tests [24]. Moreover, results were compared with 2 specimens of beams reinforced with steel bars.…”