## 5 Discussion  
The results of this study clearly confirm that tapered foundations offer superior performance over flat or shallow counterparts of an equivalent base area. This is primarily due to increased side resistance and reduced stress concentration beneath the footing, as consistently demonstrated in both experimental and numerical models. These findings align with the conclusions of [PERSON] [16], who emphasized that conical geometry enhances vertical load distribution and improves bearing capacity across a range of soil conditions. Likewise, [PERSON] and [PERSON] [17] showed that in sandy soils, tapered profiles significantly reduce settlement by mobilizing broader failure surfaces, a principle that was validated in our cone-top pile test results. The enhanced performance of the cone-top pile foundation--notably its lower settlement values and higher load tolerance--was further supported by [PERSON] and [PERSON] [18], who demonstrated that deeper embedment and conical shaping improve undrained capacity in clays. In our study, the optimized embedment depth and cone base angle were crucial for maximizing soil resistance while preventing extrusion, particularly under increased vertical loading. Field observations confirmed that most consolidation and stress dissipation occurred within a depth of 1.2-1.3 m below the conical base, aligning well with theoretical stress-dispersion models and validating the assumed compressible zone used in our settlement calculations. The beneficial influence of tapering and base roughness on bearing capacity was further supported by the findings of [PERSON] et al. [20], whose FELA-MARS model showed that roughened conical bases provide enhanced shear resistance and stress transfer. In our field tests, this translated to better stability of cone-top foundations even under significant horizontal tensile strains, which increased settlements by up to 19% for conventional foundations. The cone-top system, in contrast, maintained structural performance without approaching failure thresholds. Recent data-driven studies, such as those by [PERSON] et al. [21] and [PERSON] et al. [22], have highlighted the impact of soil heterogeneity and anisotropy on the bearing behavior of conical footings. Although this study does not focus specifically on anisotropy, the robustness of the cone-top pile design across variable soil conditions supports their conclusion that such geometries perform reliably when soil strength varies with depth. The accuracy of our axisymmetric PLAXIS simulations, especially when refined around the cone-shaft interface, further supports the use of numerical modeling in predicting load-settlement behavior in complex soil profiles. In terms of lateral stability, the present foundation design benefits from a key structural enhancement: the integration of a pile shaft into the conical base. This configuration not only provides deeper load anchorage, but also mobilizes additional shaft friction. Whileour focus was primarily on vertical loading, this concept draws direct relevance from [PERSON] and [PERSON] [24], who showed that piles embedded in sloping clay under lateral load exhibit distinct advantages in displacement control when designed for complex soil geometry. Therefore, the cone-top pile may offer increased resistance not only to vertical loading, but also to horizontal deformation in sloped or deformable terrains. Furthermore, the inclusion of a rolling joint between the cone and superstructure enhances the system's adaptability under horizontal soil movement. This innovation reflects similar design logic, as seen in [PERSON] et al. [23], who showed that precast micropile systems with flexible joints maintain high performance in layered soils under both static and dynamic loading. Similarly, the rubber-steel interface in CHFRF foundations studied by [PERSON] et al. [19] reinforces the value of introducing flexible connections to dissipate stress and reduce earth-pressure transfer during cyclic loading.