Sustainability analysis of sandstone using smart material by EMI approach

In India, sandstone was broadly used to construct structures like Agra Fort, Red Fort Delhi, and Allahabad Fort. Around the world, many historical structures were collapsed due to the adverse effect of damages. Structural health monitoring (SHM) is very useful to take appropriate action against the failure of the structure. The electro-mechanical impedance (EMI) technique is used to continuously monitor the damage. A piezoelectric ceramic (PZT) is used in the EMI technique. PZT is a smart material used as a sensor or an actuator in a certain specific manner. The EMI technique work in the 30 to 400 kHz frequency range. This technique helped to analyze the hairline crack, location, and severity of damage to structural elements. A 10 cm length and 5 cm diameter sandstone cylinder was used in the experimental work. An electric marble cutter was used to create the artificial damages of 2 mm, 3 mm, 4 mm, and 5 mm respectively along the length, at the same place in specimens. The conductance signature and susceptance signature were measured for each depth of damage. The comparative result of healthy and damaged state with different depth were concluded based on the conductance signature and susceptance signature form the sample. Statistical methods like root mean square deviation (RMSD) is used for the quantification of damage. The sustainability of sandstone has been analyzed with the help of the EMI technique and RMSD values. This paper motivates the application of the EMI technique to the historical building made of sandstone as key material.