# A Practical Group Symbol and Group Name Approach (PSNA) according to EN ISO 14688-2:2018
## 6 Conclusions  
In the present study, PSAA was developed for the identification and marking of symbols of soil mass based on EN ISO 14688-2:2018 [21]. Because EN ISO 14688-2:2018 does  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Method** & **Soil** & **Group Symbol** & **Group Name** \\ \hline \multirow{3}{*}{PSAA} & Gravel & 23 & 46 \\  & Sand & 23 & 46 \\ \cline{1-1}  & Fines & 9 & 63 \\ \hline \hline \end{tabular}
\end{table}
Table 7: Number of total group symbols and group names for PSAA.  
not provide specific percentages for the classification, it is not feasible for a user to utilize EN ISO 14688-2:2018 to classify soil comprehensively, including the assignment of group name and group symbol. Within countries that are members of the European Committee for Standardization (CEN), the national standard was withdrawn in cases where it conflicted with EN ISO 14688-2:2018. Therefore, many countries need a comprehensive method, but EN ISO 14688-2:2018 cannot close this gap owing to the use of general principles. Hence, this study proposed an identification and marking method for soils based on EN ISO 14688-2:2018. However, to accurately classify soil, it is necessary to possess comprehensive boundary ratios. Thus, the utilization of ASTM D2487-17e1 [25] proved to be beneficial in facilitating the progress of this study. With this proposed soil marking approach, a detailed classification, marked group symbols and group names of soils were provided.  
In order to provide appropriate engineering solutions, geotechnical engineers must initially undertake comprehensive descriptions and classifications of the soil in question. Understanding the relative quantities of soil particles within a soil mixture is essential for accurately resolving geotechnical problems. Therefore, a detailed description is crucial in understanding the engineering behavior of the soil. However, a detailed classification cannot be produced using the EN ISO 14688-2:2018 standard. The approach proposed in this study aims to overcome this limitation.  
The soil definition in PSNA v.1.0 provides great convenience to the user. PSNA v.1.0, which is currently based only on EN ISO 14688-2:2018 and ASTM D2487-17e1, is a program that is open to development. Additionally, it can be defined and evaluated according to different standards for further studies. This approach helps engineers to use the same soil identification principles and to understand, describe, and interpret the material and its results. A precise and comprehensive depiction of soil characteristics also enhances effective communication among geotechnical engineers.  
The contribution of the study is to provide an approach that strengthens the usability of the EN ISO 14688-2:2018 standard and allows for the detailed evaluation of soil particles.  
The approach proposed in this study can be a valuable reference when revising the standards and can be developed further with novel diagrams and charts.  
The author fully believes that this approach is constructive research that can provide immense benefits and great contributions to the literature. The method proposed in this study is expected to be extensively utilized in practical applications.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app132111964/s1](https://www.mdpi.com/article/10.3390/app132111964/s1)]([https://www.mdpi.com/article/10.3390/app132111964/s1](https://www.mdpi.com/article/10.3390/app132111964/s1)).  
This research received no external funding.  
Not applicable.  
The author gratefully thanks [PERSON] for his help while developing macros in Excel.  
The author declares no conflict of interest.