## 4 Results and Discussion
### Discussion  
Solid waste generation around the world has become an area of concern due to disposal problems. The PG generated from the fertilizer industry is no different. Although a lot of research has gone into its potential use in construction materials, its reutilization levels have been low. This could be due to the presence of naturally occurring radioactive materials in the waste [5; 6; 12; 41]. However, with the Atomic Energy Regulation Board of India providing approval for the use of PG in construction [42], the research into the reuse of PG got a significant boost. Despite the approval, the reuse of material with traces of radioactive elements may have led to skepticism among construction industry professionals as well as common people. This is where its valorization in soil stabilization activities can prove comparatively beneficial, as it goes below the ground, thereby reducing the apprehensions of construction professionals. Lime-stabilization has been the go-to method for improving poor soils, especially expansive clays. The use of PG in soil stabilization has gained significant attention in recent years both as a primary stabilizer as well as an auxiliary addendum. There are a good number of scientific investigations that use the combination of lime and PG. However, the use of scientifically established lime contents of ICL and OLC, along with PG as an auxiliary addendum has not been given an in-depth study. By comparing three different lime contents with their optimal PG dosage, the present study has attempted to bring out the ideal range of lime content that needs to be utilized for obtaining maximum strength benefits when utilizing PG as an auxiliary additive. Moreover, the mineralogical investigations have also supported the strength results revealing that the maximum benefit of PG valorization can be obtained when lime dosage it closer to ICL rather than OLC, thereby reducing the lime requirement as well. This, along with earlier studies, has also proved that PG accelerates the strength gain by hastening the pozzolanic reactions. The mineralogical investigations in the present study have also supported this through changes noticed in peak intensities of soil minerals and new products formed due to the progress of pozzolanic reactions. The results of this investigation can prove useful in subgrade stabilization for road and railway projects wherein quick strength gain can be very beneficial in saving project execution time and cost. The current investigation focused on lime contents LICL, ICL and OLC. The course of future investigations can focus on identifying whether any variation in lime content between ICL and OLC can further augment the performance of lime-PG blended stabilization. Moreover, the application of this blend in road projects also requires durable performance. Future investigations can also focus on wetting-drying as well as freezing-thawing resistance of ICL- and OLC-stabilized soil modified with PG. This can further strengthen the knowledge of field practitioners in their application of the right amounts of lime and PG that can also resist variation is subgrade moisture contents due to changes in weather conditions.