Response of Organic Lime Mortars to Thermal and Electrical Shocks Due to Lightning Strikes

Abstract

Lightning strikes are prevalent and inevitable natural phenomena that might cause damages during interaction with building structures and, in some cases, culminate in fires. During the last decades, several lightning strikes have caused considerable damages to cultural and heritage buildings. Furthermore, recent studies indicated a plausible connection between climate changes due to global warming and variations in the frequency and intensity of lightning. The evaluation of the structural efficiency and resilience of cultural buildings to global changes and natural risks appears significant in the light of the current scientific debate. This research aims at the assessment of lightning strikes’ effects on ancient heritage binding materials through the characterization of their thermal and electrical conductivity properties. This study focused on the performance evaluation of green and low-cost mortars based on the use of organic additives. Lime samples were reverse engineered by using a mixture of organics (fig, jaggery, black grape, banana, kadukai), which comprises the most common additives used in traditional Indian mortars. The reliability of the organic mixture in enhancing the resilience of masonry to lightning strikes was analyzed by using electromagnetic field simulation.

Modeling and Assessment of Lightning Hazards to Humans in Heritage Monuments in India and Sri Lanka

“…Accordingly, direct strike and aborted upward leader cases have been analyzed using the electrostatic model while the other three methods have been examined using the current model. Equations for the electrostatics and current model are indicated in (7) and (8).…”

“…Preservation of cultural heritage monuments which are invariably tall (structures had been built in ancient times by emperors either to commemorate their victories or constructed as places for religious congregation and worship) has become a challenging task since they are vulnerable to pollution, environmental hazards (chemical effluents from industries), fatigue of structural materials etc. In this context, it is also essential to recognize that detailed studies carried out in [7,8] summarize a few of the major lightning strikes that have been reported to have caused substantial damages and deformation of the heritage structures, more so on world heritage monuments of importance. On the other hand, in a similar vein, it becomes pertinent to ascertain the human fatalities associated with lightning strikes both globally as well as from the context of Indian and Sri Lankan perspective, since it is obvious that both countries share a rich tradition of a large number of heritage sites of worship related to various religious faiths.…”