## 3 Results  
### Primary Assessment and Testing  
#### 3.1.1 Small-Scale Test Analysis  
The fractions were compared to the positive and negative controls and against each other. The average of the overall measurements that showed a mean value < 0.05 (\(p\) value) indicated that the result was significant and supports the improvement in the strength characteristics. The methodology applied is a fast, reliable, and cost-effective screening tool for early assessment of structural properties allowing for prioritisation and selection of microbes and microbial components. This study shows that one or more components (fractions) of the fermentation material improved resistance to: compression, abrasion, erosion, and water absorption properties of the selected soils, designated as soil type i and soil type ii. Evaluation of Compression Resistance  
The assay was based on the ability of a potential bio-stabiliser to resist compression, which would reduce deformation of the material or rutting when exposed to an applied stress. This would indicate maximum achievable strength characteristics. As illustrated in Figure 3 the fractions that showed improved compression resistance in comparison to the negative and positive control exhibited compression resistant properties. Fractions c2 (10.06 \(\pm\) 0.53%, \(p\) value < 0.0001), using soil type i, showed a high resistance to compression stress of >10 MPa strength compared to the positive control (8.52 \(\pm\) 0.83%, \(p\) value 0.0003). Moreover, with soil type ii, fraction a2 (16.15 \(\pm\) 0.43%, \(p\) value 0.0003) compared to the positive control (9.56 \(\pm\) 0.93%), and statistical significance (\(p\) value < 0.0001). Evaluation of Water Absorption Properties  
The assay was based on the ability of a potential bio-stabiliser to inhibit absorption of water, which would thereby limit loss of material and maintain form when exposed to external water penetration. The fractions that showed lower water absorption coefficients (Aw) indicated reduced absorptive properties in comparison to the negative and positive control water resistant properties. Fraction f1 (soil type i) (1.097 \(\pm\) 0.12 kg\(\cdot\)m\({}^{-2}\cdot\)s\({}^{-1/2}\)) shows mean difference compared to the positive control (0.401 \(\pm\) 0.01 kg\(\cdot\)m\({}^{-2}\cdot\)s\({}^{-1/2}\)), with statistical significance (\(p\) value 0.0004) Figure S6 (Supplementary Material). Whereas, fraction b (soil type ii) indicated the best water absorption properties, 0.817 \(\pm\) 0.06 kg\(\cdot\)m\({}^{-2}\cdot\)s\({}^{-1/2}\), mean difference compared to the positive control (0.282 \(\pm\) 0.01 kg\(\cdot\)m\({}^{-2}\cdot\)s\({}^{-1/2}\)), and shows a statistical significance (\(p\) value \(<\) 0.0001). The fractions show statistically high absorptive property in comparison to the positive control (i.e., therefore the hydrophilic versus hydrophobic nature of fraction/s and its cohesion effect may vary with the two soils). Neither  
Figure 3: Compression breakage point showing (**a**) soil type i and (**b**) soil type ii, treated with fractions from the vegetative phase & sporulation phase. Results expressed as mean \(\pm\) SD; N = 6; \(p\) value (two-tailed) \(p\)\(<\) 0.05 vs. control. wearing course nor the subgrade (to a lesser extent) should deform under applied loads in either wet or dry conditions. A lack of stability results in general deformation, rutting, or potholes [22]. Therefore, the following best performing prototypes that exhibited resistance to water are presented. As shown in Figure 4, the untreated dolerite and weathered granite showed <40% resistance to water and completely disintegrated after 6 min due to weak adhesion among the soil particles, and many fine particles were dispersed. Comparatively, the treated soils with 2.5% stabiliser (samples a, b2 and e2 tested on dolerite soil; and samples a, and d tested on weathered granite soil) improved significantly (\(p\) value < 0.05) (refer to the statistical analysis Tables S4 and S5 (Supplementary Material)).