PREDICTED OVERALL STABILITY OF EMBANKMENT ON VERY SOFT SOIL REINFORCED BY BAMBOO PILES BASED ON FULLSCALE TEST DATA

Abstract

Local government has built a coastal dike for countermeasurebig waves from the seashore in
North Maluku.As consequence, the condition of the ground has consisted deposit very soft soils. As far as, a
traditional foundation system such mattress and bamboo pile installed to increase bearing capacity of the soft
ground. However, theIndonesian guidelines recommended to design embankment using trial data from the
field test data,it is to difficult to applied by local engineers and government. Therefore, theproposal of
research is a simple method using reasonable physical equations for predicting overall stabilityof dike on
very soft soil based on full-scale tests on the traditional foundation, which modeled a mattress from soil
admixed cement on the geo-bamboo,and its supported by bamboo piles. In which are modeled the mattress
contained soil with cement 10%, thickness, Dm of 22 cm, bamboo pile installed by diameter, d of 8.1 cm,
spacing, s of 3d, length, L of 1.10 m.In order to design the parameters of coefficient of friction αp for overall
stability, concrete blocks were placed on the mattress reinforced bamboo piles. Finally, the overall stability
such factor of safety, Fs is found more than 1.2 for design height of embankment, Hb less than 1.0 m.