# Electromechanical Behavior of Afyonkarahisar Clay Under Varying Stress and Moisture Conditions
## 6 Limitations  
Despite its strengths, this study acknowledges several limitations that should be considered when interpreting and applying the results to broader contexts.  
Firstly, based on geomechanical characteristics and laboratory test data, the investigated clay from Afyonkarahisar most closely corresponds to the CH classification (high plasticity clay) according to the Unified Soil Classification System (USCS) and to CIH according to the Classification System ISO 14688-1. While this provides a consistent basis for analysis, it inherently limits the generalizability of the findings. To broaden the applicability of the research outcomes, future studies should include other clay types with varying mineralogical compositions and plasticity characteristics, as outlined in Table 2.  
Secondly, the experimental program was limited to uniaxial compression tests. Although these tests are valuable for initial material characterization, they do not fully represent the complex stress conditions encountered in situ. For a more comprehensive understanding of clay behavior under realistic geotechnical conditions, future investigations should incorporate direct shear and triaxial tests. The integration of these methods with electromechanical measurements could reveal important interdependencies between mechanical loading modes and electrical responses.  
Thirdly, while laboratory testing allows for controlled experimental conditions, it cannot fully replicate field environments. Therefore, to assess the practical relevance and predictive value of the laboratory results, complementary field investigations are essential.  
Additionally, the empirical equation used to describe the dependency of the undrained shear strength to unconfined compressive strength ratio on the normalized water content involves material-specific parameters. These parameters must be calibrated individually for each representative soil type to ensure accurate and meaningful predictions. Without such calibration, the applicability of the empirical relationship to different soils remains limited and may lead to misleading interpretations.  
Lastly, it should be noted that Figures 8-11 present results based on only three data points, each corresponding to uniaxial compression tests conducted at carefully selected moisture contents (10%, 20%, and 30%). These moisture levels were chosen based on preliminary material characterization and represent typical field-relevant conditions for high-plasticity clays. While a larger dataset could enhance the statistical robustness of the fitted curves, the primary aim here was to illustrate the general trends and qualitative relationships between moisture content, shear strength, and electrical resistivity. Future work will consider denser sampling of moisture conditions to improve the resolution and reliability of the fitting analysis.  
These limitations point to key areas for future research. Expanding the study to include different clay types, employing a wider range of mechanical testing methods, and validating findings under field conditions are crucial steps toward a more complete understanding of the electromechanical behavior of clays in engineering contexts.  
Conceptualization, A.R.B., S.G., B.Z. and T.B.; methodology, A.R.B., S.G., B.Z. and T.B.; laboratory experimental work, A.R.B. and S.G.; formal analysis, A.R.B., S.G., B.Z. and T.B.; writing--original draft preparation, A.R.B., S.G., B.Z. and T.B. All authors have read and agreed to the published version of the manuscript.  
This research was partly funded by the Slovenian Research Agency (grant number P2-0268).  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The data presented in this study are available upon request from the corresponding author.  
**Conflicts of Interest:** The authors declare no conflicts of interest.