Long-Term Drainage Performance of Wicking Geotextile Based on Ultraviolet-Resistant Modification Treatment

ABSTRACT Roadbed engineering in alpine tundra environment is prone to frost heave and thaw settlement, cracking of pavement, uneven settlement, and other challenges under the action of seasonal freeze-thaw cycle. Wicking geotextile has important application value in frost damage control of roadbeds, but solar radiation, especially ultraviolet radiation, is one of the main factors leading to premature failure of wicking geotextile. In this study, different kinds of ultraviolet-resistant wicking fibers were developed by blending modification technology, and the various types of fibers were compared with each other in terms of their physical and mechanical properties, so as to obtain the optimal modified wicking fibers with the content of 2 % UV-1164 + 0.3 % B900 addition. Subsequently, a 20-day accelerated aging test was conducted on modified wicking geotextiles. The inhibitory effect of the modification treatment on the wicking geotextile indicating photo-oxidative aging was characterized by scanning electron microscope, and the effect on the mechanical properties maintenance of the wicking geotextile was characterized by tensile strength and top-breaking strength tests. Finally, a soil column drainage test was designed and carried out, based on which the horizontal hydraulic conductivity rate and 120-h drainage volume of wicking geotextiles before and after the modified treatment were predicted under the aging cycle of 40 d. The test and prediction dates showed that the hydraulic conductivity was deteriorated with the aging time, but the modification treatment could obviously inhibit the deterioration degree. Compared with the control group, the hydraulic conductivity of the modified wicking geotextile increased by about 0.35E-5 g/s, and the drainage capacity increased by 0.76 % at 200 h.