The condition of the embankment slopes in the Porong-Gempol Toll
Road project on package 3A STA 41+570 is the place for the case study to
be carried out in this research. The soil layer at the location is dominated by
clay, and the soil layer used is up to the 4th layer at a depth of 19.2 meters.
Meanwhile, the soil used for the embankment is compacted sandy loam.
The analysis was carried out using variations in embankment height ranging
from 2 m, 4 m, and 6 m.. This study analyzes the stability of the
embankment/slope using geotextile reinforcement with a computer
program, namely Bentley PLAXIS 2D V20. The analysis was carried out with
the aim of knowing the magnitude of the safe number and the potential
landslide.
The geotextile reinforcement used serves to increase the slope safety
value. On percutaneous embankment slopes, it was also found that the
embankment heights of 2 m, 4 m, and 6 m had reached the allowable safe
limit SF (Safety Factor) ≥1,25; Landslides are rare (slopes are relatively
stable) (Bowless, 1989), so for embankment height of 7 m not
recommended. In terms of land subsidence from 0 to 200 days, there is a
significant difference for the 6 m to 7 m embankment because it experienced
a considerable decrease in deformation even after being given geotextile
reinforcement, this is because the load that occurs is getting heavier from
the traffic load to the geotextile load itself. So the higher the embankment,
the higher the value of consolidation and changes in shape that occur so
that variations in embankment height are very influential in the analysis
results.

Keyword: Slope stability, Geotextile, Safety Factor, Consolidation, Bentley
PLAXIS V20