Assessment of Protection Systems for Buried Steel Pipelines Endangered by Rockfall

Abstract:  This article deals with the assessment of two different protection systems for buried steel pipelines which are endangered by rockfall. First, a gravel‐based protection system (GBPS) is investigated, that is, a pipeline buried in sandy gravel is considered. To assess the load‐carrying behavior of this structure when subjected to rockfall, a finite element (FE) model has been developed. The development and the validation of this structural model are strictly separated, that is, they are based on two physically and statistically independent sets of experiments. Subsequently, scenarios of rockfall onto a gravel‐buried steel pipe are analyzed considering different boundary conditions and structural dimensions. Following the conclusions drawn from these numerical analyses, an enhanced protection system (EPS) is proposed. It consists of gravel as an energy‐absorbing and impact‐damping system and a buried steel plate resting on walls made of concrete representing a load‐carrying structural component. The potential and the limitations of both protection systems are discussed in detail.

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