# Experimental Study on Pullout Behavior of Coir Geotextiles Based on Transparent Soil
## 4 Conclusions  
In the present study, transparent soil technology was used to carry out the interface pullout test between the coir geotextile and the transparent soil. The effects of normal stress, anchorage length, and pullout rate on the interface mechanical properties of reinforced soil were analyzed. The following conclusions were drawn:  
1. The mechanical response of different pullout tests was basically similar, that is, with the increase in pullout displacement, the pullout force first increased rapidly, then slowly increased to the peak value, and then gradually decreased with the fluctuation.
2. The cohesion at the stiff-soil interface was 5.68 kPa, and the internal friction angle was 3.43\({}^{\circ}\). The interfacial friction coefficient was in the range of 0.2-0.6.
3. With the normal stress increasing from 10 kPa to 20 kPa and 40 kPa successively, the peak value of the pullout force increased from 1.8 kN to 2.2 kN and 2.4 kN successively and the thickness of the shear band increased from 13 mm to 16 mm and 20 mm successively.
4. As the anchorage length increased from 100 mm to 300 mm and 500 mm successively, the peak pullout force increased from 1.3 kN to 1.6 kN and 2.2 kN successively and the thickness of the shear band increased from 11 mm to 14 mm and 16 mm successively.
5. As the pullout rate increased from 1 mm/min to 3 mm/min, the peak pullout force increased from 2.2 kN to 2.4 kN and the thickness of the shear band increased from 16 mm to 18 mm.  
In the future, the application prospects of coir geotextiles are quite considerable. Coir geotextiles, as a renewable resource, have the characteristics of low carbon emission and high biodegradability compared with traditional geomaterials and can be used in ecological slope protection engineering, roadbed reinforcement engineering, and foundation rein  
Figure 14: The contour of particle displacement at different pullout rates. (**a**) 1 mm/min; (**b**) 3 mm/min.  
forcement engineering. Subsequently, the relevant research of this subject can be planned from the following two aspects. First of all, in terms of material performance optimization, better weaving methods, physical modification methods, and chemical modification methods can be explored to improve the strengthening effect of coir geotextiles in the soil. Second, in terms of long-term performance evaluation, long-term field tests and monitoring can be carried out in the future to evaluate the reinforcement effect of coir geotextiles in complex environments, especially under different soil types. The application research of coir geotextiles is not limited to the above mentioned, and related research needs to be further expanded in the future.  
Conceptualization, L.L. and H.L.; data curation, L.L.; formal analysis, L.L., H.L. and W.C.; funding acquisition, L.L.; investigation, L.L.; methodology, L.L.; project administration, L.L.; resources, L.L.; software, H.L.; supervision, L.L.; validation, L.L., H.L. and W.C.; visualization, H.L.; writing--original draft, H.L.; writing--review and editing, L.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (Grant No. 42207190) and the Natural Science Foundation of Hainan Province, China. (Grant No. 122 RC541).  
Not appliable.  
Not applicable.  
The original contributions presented in the study are included in the article. Further inquiries can be directed to the corresponding author.  
The authors declare no conflicts of interest.