A comparative study of red brick powder and lime as soft soil stabilizer [version 1; peer review: 2 approved with reservations]

Background: Soil has an important role to play in planning buildings because it supports the loads above it. Different types of soil with poor mechanical properties require more attention. Therefore, it is necessary to put in more effort to stabilize soil in order to improve its properties. This study aimed to compare the potential of lime and brick powder as stabilizers based on the values of California bearing ratio (CBR). Soil stabilization can be defined as the process of stabilizing soil properties by chemical or physical means to improve its engineering efficiency. The main objectives of stabilizing soil are to increase the bearing capacity of soil, to increase its resistance to weathering processes, and its permeability. Methods: In this work laboratory tests were done with disturbed and undisturbed soil samples. The proportions of lime or red brick powder additives mixed together are 0%, 5%, 10%, and 15% of the original soil sample. From the results of the laboratory tests, the soil type obtained is MH soil based on the Unified Soil Classification System (USCS). The MH soil type is a low plasticity silt soil. Results: The study's results showed that with the addition of lime and brick powder, the soil could be stabilized. In both soaked and unsoaked CBR tests, there was an increase in the CBR value for each proportion of the mixed additives. However, red brick powder had a significant increase of 15%. Conclusions: This study found a very large range of variations because of the many material requirements for each test. We suggest other researchers perform the CBR test by reducing the range of variations in the additives to get firm data and using our experimental procedure in this study for further research.