Comparative study of TEOS-consolidants for adobe building conservation

Four different consolidants for adobe buildings conservation were synthetized and evaluated. Adobe bricks materials tested from several Mining Haciendas of the seventeenth and eighteenth centuries located in Guanajuato, Mexico; these materials were characterized using XRD analysis, granulometry, porosity, moisture content, and mechanical resistance. The four consolidants synthetized are formulations based on TEOS (F1); TEOS with silica nanoparticles (F2); TEOS with PDMS-OH (F3) and hybrid consolidant formed by TEOS, PDMS, and nanoparticle silica (F4). The consolidants were tested and evaluated by porosity changes, absorption, and durability. The results show that colloidal silica improves the fulfill porosity by TEOS gels and the PDMS improves the flexibility on TEOS gel avoiding the crack. Thus, the addition of both components to TEOS gel results as an excellent consolidant treatment to adobe materials. Highlights TEOS and different additives are proposed as adobe conservation treatment. Mechanical resistance increases according to the additive consolidant treatment. The different additives shown different penetration capacity that modify the consolidant process. PDMS additive increases the chemical stability on TEOS consolidant.