Application of geotextile ropes in slope erosion protection

Abstract

Paper deals with application of geotextile ropes in erosion protection of slope of gravel pit in Nieboczowy, Poland. For protection of the slope the segments formed from thick ropes were applied. The ropes with the diameter of 120 mm were produced by the Kemafil technology. Ropes were made from strips of stitch-bonded nonwoven produced from a mixture of recycled natural and synthetic fibres and strips of wool needle-punched nonwoven. The protected slope had the length of 4 to 6 m, slope inclination from 1:1 to 1:1.8 and total area of approximately 150 m2. It will be shown that installed ropes restrain soil so there is no slope failure in protected section even in case of low soil shear strength parameters and unfavourable hydraulic conditions. Generally slope surface in protected section is without rills and gullies. This case also shows that plants are very good anti-erosion measure. Thanks ropes installed on the slope, favourable conditions for plants growth are created and maintained.

Application of Innovative Ropes from Textile Waste as an Anti-Erosion Measure

“…In the north-facing bank of the excavation on the surface of native ground, an artificial embankment with a height of approximately 4 m was formed. The embankment erected from overburden material mined during mine operation coupled with the steep slope cut in native ground was especially unstable and endangered by local sliding [ 17 ].…”

“…The effectiveness of installed ropes can be seen in Figure 1 b. As we can see in Figure 1 a, there is much vegetation, and no signs of erosion exist in the protected slope part [ 17 ].…”

“…Numbers 1, 2, and 3 in Figure 2 mark the soil sample locations, which were chosen from the left, central, and right parts of the slope (horizontally) and in the central part (vertically). Generally, the slope is well protected and covered with rich plants [ 17 ]. After 47 months following the rope installation, a second visitation of the protected location took place on 18 January 2020 (47 months after rope installation), during which two soil samples were taken from two locations of the protected slope for further analyses.…”

“…From this reason, two soil samples from every location were taken and analyzed. The specimens were marked based on location (numbers 1, 2, or 3 and letters “a” for the upper layer and “b” for the lower layer); for example, the specimen marked as “1a” was taken from location 1 from the upper layer [ 17 ].…”

“…In contrary to the slopes in Lipnik and Międzyrzecze, where the slope inclination was 1:1.5, the slope surface was a plane without slides and the ropes were invisible (buried), the slope in Nieboczowy had various inclinations (from 1:1 to 1:1.8) and the ropes in the steeper part were exposed. The analysis of slope stability presented in a previous paper [ 17 ] showed that a slope without geotextile ropes will slide. The shortcomings of the above analysis lie in determination of the physical and mechanical soil properties only on the basis of the soil liquidity index I L in accordance with [ 18 ] (not from the tests).…”