# A Comparative Study of the Pullout Strength of Geostraps and Geogrids in Reinforced Soil
## 5 Conclusions  
This study involves an experimental analysis to validate a numerical model for finite element analysis. The deviation of the experimental results from those of the numerical analysis is around 5%. The numerical model was then tested to determine the pullout strength of different grades of geostraps. The pullout performance of the M65 grade of geostrap was compared with that of a biaxial geogrid. The analysis highlights the potential of geostraps as efficient, durable, and environmentally resilient alternatives for reinforced soil structures. Based on the findings of this study, the following may be concluded:  
The M65 grade of geostrap exhibits a higher pullout resistance (15.25 kN m\({}^{-1}\)), followed by the M50 (14.5 kN m\({}^{-1}\)), M37.5 (13.4 kN m\({}^{-1}\)), and M25 (12.1 kN m\({}^{-1}\)) grades of geostraps. This wide range of pullout resistance offers ample options for different geotechnical challenges. Considering the soil type and load, the judicious use of the desired grade of geosynthetics may cut project costs and achieve sustainability goals. Based on the pullout resistance offered in sand, their applications can be listed as shown in Table 5.  
Geostraps initially exhibited greater pullout resistance in sandy soil than geogrids due to their combined reliance on friction and partial interlocking. However, the maximum pullout resistance of the geogrid (53 kNm\({}^{-1}\)) was higher than that of the geostrap (49 kN m\({}^{-1}\)). Based on the test results, the application area of both geostraps and geogrids can be determined as shown in Table 6. Therefore, it can be deduced from the findings that geostraps may prove highly effective as reinforcements for low-volume roads and backfill materials. However, in the case of high-volume roads, geogrids show more promising results for poorly graded sand.  
\begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline \hline
**Geostrap Grade** &
\begin{tabular}{c} **Maximum Pullout** \\ **Strength (kN/m\({}^{2}\))** \\ \end{tabular} & **Application Area** & **Soil Conditions** & **Remarks** \\ \hline M25 & 12.1 & Landscaping fill, shallow slope stabilisation & Well-compacted, non-cohesive to moderately cohesive soils & Suitable for non-critical zones with low shear stress and minimal sncharge & Suitable for non-critical zones with low shear stress and minimal sncharge & Suitable for non-critical zones with low shear stress and minimal sncharge \\ M37.5 & 13.4 & Light traffic embankments, shallow foundation beds & Moderately firm soils with moderate moisture & Improves bearing and settlement resistance in lightly loaded zones & Improves bearing and settlement resistance in lightly loaded zones & Improves bearing and settlement resistance in lightly loaded zones & Improves bearing and settlement \\ M50 & 14.5 & Reinforced slopes, pavement subgrade improvement & Soft to firm soils with variable moisture & Common for road-base stabilisation and slopes under moderate traffic loads & Common for road-base stabilisation and slopes under Preferred in critical areas with high loads; long-term performance is required \\ M65 & 15.25 & Embarnkments over soft soils, seismic reinforcement & Weak, compressible, or aggressive soils & & & \\ \hline \hline \end{tabular}
\end{table}
Table 5: Applications of different grades of geostraps based on their pullout capacity.  
The pullout behaviour of geostraps represents a significant advancement in geosynthetic reinforcement materials. By comparing the performance of geogrids and geostraps, a versatile and efficient solution for reinforced soil structures is provided. The findings of this study underscore the potential of geostraps to address the limitations of conventional geosynthetics, paving the way for more robust and adaptable geotechnical designs.