Specificity of the development and characteristics of mixed damage to network structures of pipeline transportation systems

Abstract

Pipeline transportation systems are used in various industries for the purpose of delivering various substances and materials to consumers. If, as the result of an accident development, a certain number of random linear elements (pipelines) consecutively fail, such scenario of events is called progressive damage. If several pipelines converging at a node fail simultaneously, such point element of the system is blocked. Progressive blocking of a certain set of nodes of a pipeline system in random order is called a progressive blocking. Simultaneous development within a system of progressive damage to linear elements and blocking of transportation nodes represents mixed damage. Mixed damage is a hazardous form of emergency, and its development causes fast degradation of a system’s transportation capabilities.TheAimof the paper is to study the characteristic properties and patterns of the progress of mixed damage affecting network structures of pipeline systems, as well as evaluating such systems’ capability to resist its development.Methods of research.The characteristics of network entities’ resilience to the development of mixed damage were identified by means of computer simulation. The nature of the effects to which a system is exposed was defined with a cyclogram, whose integer parameters indicate the alternation of the process of sequential damage of linear elements and nodes of a network structure.Results.It has been established that a correct comparison of the resilience of various network structures to mixed damage is only possible with regard to comparable facilities. For that purpose, the analyzed systems must have identical numbers of nodes, linear elements and end product consumers. Additionally, such systems must be exposed to effects with identical cyclograms. It is shown that the correlation of the resilience of comparable network structures does not depend on the specific type of mixed damage cyclogram, but is defined by the nature of the connections within a particular system.Conclusions.Mixed damage is a hazardous development scenario of an emergency situation that is associated with rapid degradation of the transportation capacity of pipeline systems. The ability of network structures of pipeline systems to resist mixed damage is evaluated based on indicators that are defined by means of simulation. A correct comparison of the resilience of various structures to mixed damage is only possible in case they are comparable. For that purpose, they must have identical numbers of nodes, linear elements and product consumers. Additionally, such systems must be exposed to damage procedures with identical cyclograms. The correlation of the resilience of network structures that comply with the comparability conditions does not depend on the adopted damage cyclogram, but is defined by the existing set of connections within a particular system.