Application of nano-pico geotechnics and nano-pico heritage spray techniques for restoring and protecting historical brick buildings

This study evaluates nanotechnology's application in restoring historical brick facades, specifically focusing on how montmorillonite clay nanoparticle spray effectively fills cracks and pores, thereby reducing porosity and decreasing water absorption. The research methodology involves controlled experiments on both historical and purchased brick samples, assessing the impact of nanospray through water absorption and porosity tests. The study seeks to mitigate surface water penetration to the bricks, as well as to fill the capillary cracks and pores that have formed due to various factors. Results indicate that nanospray successfully fills pores and capillary cracks, reducing water penetration and improving brick durability. When nanoparticles fill these pores and cracks, they effectively reduce the overall porosity and also increase the tortuosity that water vapor must take to pass through the material. By reducing the number and size of pores and making the diffusion path more tortuous, the nanoparticle treatment can increase the water vapor diffusion resistance of the brick. While reducing water absorption is beneficial for protecting the brick from water damages, breadthening of historic masonry is necessary, meaning it must be able to absorb or release moisture by changing the humidity level. Using nanoclays as Nano-Pico Getechnics (NaPG) and Nano-Geotechnics (NaG) techniques can consider the balance between reducing water absorption and maintaining sufficient vapor permeability (breathability). clay nanoparticles can fill the pores without completely blocking them, thus allowing vapor to pass through. This study contributes to advancing sustainable restoration practices to assess the long-term effects and environmental adaptability of nanospray applications. This nanotechnology approach is chosen not only for its high efficiency in protecting brick facades but also for its economic viability and environmental compatibility, classifying it as a form of "green restoration" or "sustainable restoration".