Enhanced drainage performance of PVF-wicking geosynthetics: Development and experimental assessment

An enhanced geosynthetic material, PVF-wicking geosynthetic (PWG), was developed to improve the performance of the wicking geosynthetic product family, e.g., the wicking geotextile (WG). The PWG was made by coating deep-grooved wicking yarns and reinforcement with the layered polyvinyl alcohol formaldehyde (PVF) high-absorbent materials. The drainage performance of PWG was assessed through beaker drainage tests and soil column tests. The results of the beaker drainage test and SEM images indicate that PVF does not obstruct the deep-grooved yarns. It is found that, by facilitating efficient water absorption, storage, and transfer as a transit layer between the subgrade and wicking yarns, PVF plays a crucial role in enhancing the drainage capabilities of the geosynthetic material. PWG outperforms WG in terms of drainage efficiency under both static and cyclic loading conditions. The mechanism of the drainage improvement by PWG under cyclic loading is that the excess pore pressure within the PVF layer accelerates the water transfer from the pores of the PVF into the grooves of yarns. PWG, included with reinforcement, exhibited comparable interface characteristics to WG, with the potential to meet the requirements of soil stabilization. The remarkable drainage efficiency of PWG underscores its potential for practical applications.