Enhancing Local Building Materials with Sandstone and Alkaline Solution: A Comprehensive Study on Thermal and Mechanical Characteristics

The implementation of global policies focused on sustainable development aims to valorize local materials and reduce construction costs, as well as energy consumption for heating and cooling. It is important to note that the use of local materials in construction also has important environmental benefits, such as the reduction of greenhouse gas emissions related to the transportation of materials and better integration into the local environment. In this context, the objective of this study is to develop earth bricks made from local materials stabilized by sandstone and alkaline solution (sodium hydroxide and sodium aluminosilicate). In order to characterize the materials, techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR), and energy-dispersive X-ray (EDX) were used. Chemical analyses of the sandstone revealed high Quartz content with accurate peaks and angles. To evaluate the thermomechanical properties, specimens were prepared with varying percentages of ground sandstone (from 0 to 20%) with a proportion of 1.5% alkaline solution. The results showed that the bricks stabilized by the sandstone and alkaline solution exhibited superior thermal and mechanical properties compared to the unstabilized earth bricks. In particular, shoot-up in compressive strength and thermal conductivity was observed with increasing concentration of sandstone and alkaline solution. This study demonstrated the feasibility of developing geo-sourced compressed earth bricks with local materials to help reduce construction costs and energy consumed for heating or cooling. In addition, the use of sandstone in the manufacture of compressed earth bricks can also contribute to the preservation of natural resources and environmental protection.