A Comprehensive Framework for Direct Lightning-Structure-Human Interaction Modelling in Heritage Monuments and Safety Assessment

Abstract

Lightning is a perilous and unavoidable event of nature that presents major deleterious consequences on humans, tall structures, electrical power systems, forests, etc. Though several research studies have been carried out to analyse the sufficiency of a Lightning Protection System (LPS), very few research findings have been reported to assess the extent of risk due to lightning-human interaction in the vicinity of tall structures. This research aims at carrying out detailed modelling and simulation studies of LPS for heritage structure. Several current waveshapes as stipulated in IEC 62305 are modelled appropriately and presented to the electrical equivalent circuit representation of a heritage monument in South India (Brihadisvara Temple) to ascertain the impact of lightning parameters on heritage monuments. In addition, to assess the effectiveness of the earthing system, detailed earthing models during lightning is developed to assess the role played by aspects such as soil resistivity (single and double), earth electrode dimensions, nature of elements in the equivalent circuit, etc. Further, the role of lightning strikes on human due to step and touch potential is ascertained by formulating a lumped electrical equivalent model of human to assess its role and impact on dry and wet skin.