The mechanics of historic (South Indian) temple architecture: Stone masonry walls

In one of our previous blogs we had said that ‘historic buildings are constructed of natural materials and hence they behave differently’. In this blog we discuss ‘what is different’ through one example: stone masonry in construction of historic structures, particularly South Indian temples.  Typically in South Indian temple architecture stone masonry is constructed either as a single veneer or as a three veneer composite masonry. By single veneer I mean masonry with single layer of stone blocks in regular bonding. Composite masonry has inner and outer veneers in stone masonry and a core filled with rubble and mud or in few cases brick masonry in lime mortar.  In both types the important point to note is that the veneers are of dry stone masonry – meaning there is no mortar used in construction of the stone walls. Then how are the stones joined? How do they stay in place? Would the blocks not collapse with a strong push to the wall? What happens in case of earthquake? Well, th

The mechanics of historic (South Indian) temple architecture: Pillars

Besides fulfilling the spiritual/religious needs of devotees are historic South Indian temples only sculptural marvels? What else can they teach us? In this post I limit the discussion to pillars and address other elements in subsequent posts. The question of what a temple structure can teach us became relevant after a visit to one of the many large temple complexes in Tamil Nadu. The temple's carved pillars are justly famous, which however led to a problematic outcome-the pillars were seen as free-standing sculptures with no other purpose than ornamentation, completely sidelining their essential functional role. At a pragmatic level from a conservation standpoint I found this problematic as the probably historic stone floor and any (un-carved) available portion of the pillar and beam arrangement, including the capitals, had been drilled into, in order to insert electrical wiring, conduits, tube-lights, switchboards, meter boards, and floodlights to highlight the 'glorious c

Understanding the science of historic buildings

What is a historic building? Historic buildings are structures built years ago, ranging from few decades to many hundred years. They are typically constructed using naturally occurring or locally made rather than large-scale manufactured materials. Therefore they behave differently (for instance how they bear their own weight and that of the building's users: read our blog on this) compared to contemporary buildings which are built using industrial grade materials like steel, cement, and concrete.  In the short term using modern materials on a historic building may not seem problematic but over time their usage would substantially reduce the lifespan of a historic building. This is because the composition and properties of both are completely different. For example, historic buildings would have walls of stone, brick, or even mud and not concrete or breeze blocks. They would have lime as both mortar (material binding wall components) and plaster (finishing material for walls)