PENGARUH KADAR AIR TERHADAP KUAT GESER PADA TANAH LANAU

Abstract

Landslide disaster such as bank slide or embankment slide often occurs.
This it begins with a simple problem, that is infiltration of rain water into soil
causing the decrease of soil strength resulting in collapse. The research tries
to explain the water influe'nce at the shear strength of soil to find out how much
water content may induce soil collapse.
This experimental research was conducted in the soH laboratory using
mud from Imogiri, Bantul conditioned in several water contents (from 10% to
500/0) and direct shear tests were then applied. This experiment would produce
CD (internal soil shear angle), c (soil cohesion), and finally slide off soil safety
factor (F).
This research has resulted:
1. at a low water content (10%
) the CD soil is low, the CD increases by increasing
the water content, but the next increas of water' content causes a decrease
of CD. The maximum CD (32.5°) reaches at 23% of water content.
2. at a low water content (10%) the c soil is low, the c increases by increasing
the water content, but the next increasing of water content causes a decrease
of c. The maximum c (0.076 kg/cm2
) reaches at 22% of water content.
3. at a low water content (100/0) the F soil is low, the CD increases by increasing
the water content, but the next increasing of water content causes a decrease
of F. The maximum F reaches at 21% of water content.
Key words: mud, soil, water content, shear strength, cohesion, land slide.