# Improving Geotechnical Properties of Expansive Subgrade Using Sugar Cane Molasses and Cement
## 5 Conclusions and Recommendations  
This research rigorously investigated the effectiveness of sugar cane molasses and cement in addressing the challenges posed by expansive soils. An extensive array of geotechnical assessments was performed to ascertain the soil's consistency, compaction characteristics, and California Bearing Ratio (CBR) performance while taking into account its long-term stability. Moreover, molasses, being economical by-products of industrial processes, contribute to a reduction in environmental pollution when utilized in the construction of pavement subgrades. The following conclusions are drawn from this research study. 1. The values of the liquid limit declined with the addition of sugar cane molasses and cement up to 12%. For the stabilized soil, the liquid limit value decreased from 40% to 27% compared to the unstabilized soil. The values of the plastic limit also slightly declined with the addition of sugar cane molasses and cement up to 12%. Additionally, the values of the Plasticity Index decreased with the addition of sugar cane molasses and cement. 2. The values of MDD increased with the addition of sugar cane molasses and cement up to 12%, while the values of OMC decreased with the increasing percentages of sugar cane molasses and cement in the soil sample. 3. In the unconfined compression test, it was observed that the compressive strength of the stabilized soil increased by 64.7% with the addition of sugar cane molasses and cement up to 12%, after curing for 7 days, compared to the strength of the native soil. Soil treated with molasses exhibited a plastic nature, while soil treated with cement showed a brittle nature, with shrinkage cracks observed. The addition of molasses to cement reduced the soil's brittleness. 4. The addition of 12% sugar cane molasses to 12% cement increased the CBR value from 4.2% in the native soil to 12.3% in the stabilized soil and reduced the swell value from 9.66% in the native soil to 3.82% in the stabilized soil, after curing for 7 days. Thus, the geotechnical properties of the soil improved. It is recommended to further study the chemical interactions between cement, sugarcane molasses, water, and expansive clay soils, as the use of this mixture for soil stabilization is relatively new. Additionally, the effect of varying curing periods on soil properties should \begin{table}
\begin{tabular}{l l l l} \hline \hline
**Stabilizer** & **Advantages** & **Disadvantages** & **References** \\ \hline \multirow{3}{*}{Molasses and Cement} & 1. Cost-effective & 1. Increases plasticity at high levels & \multirow{2}{*}{[PERSON] et al., 2020} \\  & 2. Readily available & 2. High carbon footprint of cement & [9] \\ \cline{1-1}  & 3. Improves strength & & \\ \hline Microbial Induced Calcium & 1. Environmentally friendly & 1. Requires specific conditions for & \\ Carbonate Precipitation & 2. Self-healing properties & bacterial activity & \\ (MICP) & 3. Enhances durability & 2. Slower to act in large-scale projects & \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Comparison of advantages and disadvantages of molasses–cement stabilization vs. microbial-induced calcium carbonate precipitation (MICP). be investigated. Incorporating non-destructive testing methods, such as ultrasonic pulse velocity (UPV), would provide insights into internal structure integrity and crack formation. Evaluating the performance of stabilized soils under different environmental conditions, such as freeze-thaw and wet-dry cycles, will help determine the adaptability of this method across various climates and regions. [PERSON] performed the field and lab tests, investigation, and writing--original draft preparation; [PERSON] contributed to the conceptualization, methodology validation, and writing--review and editing; [PERSON] contributed to writing--review and editing; [PERSON] supervision and project administration. All authors have read and agreed to the published version of the manuscript. This research was funded by the Ministry of Science and Technology of China, Grant No.