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In addition to creating environmental threats, the leakage and entrance of chemical fertilizers into soil, which is possible in various ways, dramatically changes the physical and mechanical properties of soil. Furthermore, clay soils in the vicinity of monoammonium phosphate (MAP) contamination show substantially negative behavior, thus, improving the engineering geological factors of soil has become a huge challenge for engineers. Extensive programs such as triaxial compression test, consolidation test, compaction test, Atterberg limits, and collapse tests, in addition to X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) were performed on samples containing 10%–30% MAP over 7 days, 1, and 3 months. The mentioned trend was repeated when 0.5%–3% nano A (Al2O3 in alpha phase), nano F (Fe2O3 in alpha phase), and AF in form of a nanohybrid were added to soil which had been contaminated by MAP. Gained reports demonstrated significant declines in maximum dry density, plasticity index, and shear strength of contaminated soil when compared with natural soil. Conversely, increases in liquid limit, plastic limit, consolidation settlement, as well as soil collapse index were observed. Furthermore, a decrease in the amount of minerals in the XRD results and the formation of a flocculated structure in the SEM images in MAP-contaminated soil are evident. According to microstructural analysis, adding nano A, nano F, and AF nanohybrid as an improvement phase caused remediation of the soil structure and created cementation bonds between soil particles, thereby increasing the maximum dry density and soil shear strength, and decreasing the consolidation settlement and soil collapse index. Therefore, the use of AF as an efficient additive to remediate physical and mechanical properties of soils that have been contaminated with MAP, and to decrease the geological hazards of these kinds of contamination is recommended. [ABSTRACT FROM AUTHOR]

The writers appreciate the discussers' recognition of the pioneering and novel nature of the original work, which provides a unified effective stress equation for all types of soils under all saturation conditions. However, the discussers fail to appreciate the importance of the roles of soil water adsorption mechanisms in soil water retention and effective stress, given the ample experimental evidence presented in our work and other previously published work. Instead, they raise some points, which are academically thought-provoking notions that are largely reflections of the misunderstanding of the importance of the soil sorptive potential (SSP) concept and the roles of SSP in the effective stress in soils, as detailed subsequently, following the order outlined by the discussers. The discussers consider that the sole mechanical energy in soil water is capillary pressure as they state "That [capillary water] is presumably why many researchers have previously suggested that capillary water, solely, plays a role in the mechanical behavior of unsaturated soil.". [Extracted from the article]

As discussed by Been and Jefferies, normally consolidated soil specimens with the same HT ht exhibit similar consolidation stress-normalized stress-strain-strength behavior (i.e., similar stress paths and critical state shear strengths). Consider a soil specimen at the preshearing effective vertical stress, HT ht , after unloading from a maximum effective vertical stress, HT ht . [Extracted from the article]

Das and Deb ([5]) argued that the stress concentration ratio (SCR) increased as the modular ratio (the elastic modulus of support pile and soft soil, i.e., HT ht ) increased. The HT ht was derived about 10,000 from the original Table 1, and the monitored SCR reached a maximum value of 6.6 at the end of embankment construction shown in Fig. In practice, HT ht could be calculated using the HT ht method ([9]; [12]), the HT ht method (the effective stress method, [17], [15], [16]), or the HT ht method ([13]). [Extracted from the article]