This paper presents a numerical stability analysis to the failed case of a soil gabion retaining wall on the riverbank due to a heavy storm experienced. The UUU and SUU triaxial compression tests are performed first to study the influence of soils confined with woven and non-woven geotextiles at the relative density of 95%, 90%, 85%, and 80% on the strength and stiffness. Then, a series of the numerical analyses are carried out under (1) normal river condition, (2) storm river condition, and (3) drawdown condition. The results from analyses show that the soil gabion retaining walls are stable but appear a large movement outward under storm and drawdown condition. The results of the analyses are quite similar to those of failed case observed.
Gabion walls have been used in the construction of erosion protection works, earthen embankment retaining walls for slope stability, and hydraulic structures. The advantages of gabion include very porous, flexible, strong, durable, reliable, easily constructed, and ecological. The gabion manufactured is usually a rectangular-shape unit which can be readily stacked into a variety of geometric configurations. The gabion unit is fabricated by the wire coated with polyvinyl chloride to prevent corrosion. The unit is available in 2, 3, and 4 meters lengths, 1 meter widths, and 1 meter heights. They are subdivided into cells, each cell being 1 square meter in size. The gabions are usually filled with stones which require qualities of weather resistance, non-friability, nondissolution, and high stiffness. However, the stones in such requirements are of shortage gradually, and soils with gravel are used instead. A term of soil gabion is named in this paper. The difference in between is that the soil gabion requires a bag fabricated by a geotextile with highly UV resistance placing into the wire-cell unit before filling the soils.
