## 4 Discussion
The initial water contents (Wc) of soil were chosen to be below (Wc = 40%) and above (Wc = 50%,) the liquid limit of the soil in order to investigate the effect of different water contents on low plasticity soil after homogenization and with various disintegration times. The D\({}_{50}\) was 9 mm for the non-homogenized soil specimen with 40% water content (below the liquid limit of the soil). After the natural soil was homogenized for 10 to 20 s, the D\({}_{50}\) was decreased to 6 mm. Conversely, for the wet soil specimens with an initial soil water content above the liquid limit (50%), the D\({}_{50}\) was 16 mm after homogenized for 7 s disintegration time. In contrast, the D\({}_{50}\) ranged between 6 and 7 mm for the air-dried specimens prepared at 15 and 30 s disintegration times, respectively and with an initial water content above the liquid limit. The passing percentage for the air-dried specimens was significantly higher compared to the wet specimens prepared with the same disintegration time and initial water content (50%), as shown inFigures 12 and 13. Due to the low plasticity properties of Soil 4, the variation between the wet and air-dried specimens was related to the high-water content of the soil, which made the wet soil particles adhere to each other after disintegration and stick to the sieve openings. This clearly showed the effect of water content in low plasticity soil. Therefore, the proper disintegration time for Soil 4 was mainly affected by the variation in the initial water content. When the water content was below the liquid limit of the soil, the appropriate disintegration time ranged between 15 s and a maximum of 30 s, while for soil with a high-water content (above the liquid limit) the disintegration time should be as low as possible and should not exceed 17 s.  
The agglomeration of particles after the homogenizing process was explained by the increased interaction forces between particles, leading to the formation of clusters as a result of how the particles adhere to each other [34]. The following mechanisms can lead to a rise in the agglomeration of particles for various material types [35]:  
* Mechanical interlocking: this mainly occurs if the material's particles are long and thin in shape, leading to large masses becoming completely interlocked. * Surface attraction: force between soil particles can increase the substantial bonds between particles. This effect is more pronounced in very fine particles (with less than 10-micrometre diameter) due to a high ratio of specific surface to unit volume. * Plastic welding: this occurs due to the development of very high pressures on an extremely small surface area between irregular particles. * Electrostatic attraction: the movement of the particles is caused by the electrostatic forces between particles
* Effect of moisture: Moisture has the effect of raising the surface tension effects by collecting near points of contact between particles. It may also dissolve small sections of the particles and act as a bonding agent on subsequent evaporation. A recent study reported that solid material-binder mixtures can be significantly affected by the chemical properties of the investigated solid material. For instance, the soluble salts and sulphate content can be a concerning issue regarding the efficacy of further mixing procedure with binder materials [36]. Visual and sieve analysis results indicate that, at a specified disintegration time, the soil started to have a small particle size when the agglomerated particles break into small-sized particles. Subsequently, when the disintegration time was increased, the soil particles started to adhere to each other and form clusters. This process continued until almost all the soil had accumulated into a single mass when the disintegration time was significantly increased. Table 5 summarizes the proper disintegration time to homogenize various soil types.