Resilience of Above-ground Arctic Pipelines

Abstract

The paper first introduces and describes the basic concepts of structural resilience on the example of the simplest structural element - a rod subjected to centrally applied tensile force. The very fact of the possibility of such a method of introducing fundamentally new concepts indicates that resilience is one of the intrinsic properties of mechanical systems, such as strength, durability, reliability, and can be described in quantitative terms. The novel method of structural resilience analysis used in the paper is based on two consecutive applications of the classical reliability apparatus to assessing the individual and ensemble-wise structural resilience of a physical object. First, an estimate is made of the system reliability, designed in accordance with current design standards, using the design values of loads/impacts. After that, the reliability of the same structure is examined when it falls into a beyond-the-design state. The second step analysis is nothing but testing the ability of the safety cushion, provided by the used design norms, to withstand forces that are beyond the design limits. This analysis clearly shows that resilience is conditioned by the design code used to create the system. A very conservative design code will provide the system with a large safety cushion, and with it, high resilience. A riskier code will provide the designed system with a smaller resilience. This situation can be vividly illustrated by the case of resilience analysis of pro-sportsmen: they use their capabilities to the extreme,