Physical, Mechanical and Thermal Behavior of Adobe Stabilized With “Synthetic Termite Saliva”

Abstract

Adobe is an efficient construction material for several reasons, such as its thermal comfort, sustainability, and lower energy cost, as well as the simplicity of its production and execution. However, challenges such as water absorption, capillarity, and compressive strength should be investigated to improve its physical and mechanical properties. "Synthetic termite saliva" (STS) is an excellent stabilizer with high cohesive and hydrophobic power. Therefore, the objective of this work was to evaluate the effects of STS incorporation into adobe, analyzing its physical, mechanical and thermal properties. Five treatments were studied: 0 (control); 0.1; 0.2; 0.4 and 0.8% STS by mass. These adobe samples were evaluated according to bulk density, linear shrinkage, capillarity, water absorption, thermal conductivity and compressive strength, according to Norma Técnica de Edificación (NTE) E0.80 testing using a new methodology. Linear shrinkage decreases from 2.7 to 1.91 cm with 0.4% STS. Capillarity decreases with the increasing amounts of STS. Water absorption decreased from 12.03 to 6.31% using 0.4% STS, and its mass was reduced from 779 to 19 grams. The thermal conductivity showed no differences between concentrations. The compressive strength was reduced but was still acceptable based on NTE E.080. The stabilization of the adobe using STS showed an improvement in its physical properties, mainly due to its hydrophobic power.

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