SAFETY FACTOR CHARACTERIZATION OF LANDSLIDE IN RIAU-WEST OF SUMATRA HIGHWAY

Abstract

The geological hazard is a heavy landslide often struck around Tanjung Balik area, Koto Baru
Sub District, Lima Puluh Kota District, West of Sumatra Province. Located along the highway Riau – West
Sumatra Kilometer 10-15 and the coordinates are in 00˚08'40''N- 0˚11'20 ''N and 100˚45'20''E- 100˚47'00''E.
The aim of current research work is to identify the slope safety factor that experienced landslides in the
research area. The methods used are Direct Shear Stress and safety factor analysis was used Software Slide
6.0. The results of the analysis concluded that the value of cohesion and angle of the friction are obtained
from Direct Shear Stress on the station research areas ranging from 0.261 to 0.321 kg/cm²1 with friction
angle from 11 to 20˚. Safety Factor on the research areas classified into unstable classification with the
lowest value 0.192 and the highest value 0.48.