The Effect of EPS Addition to Soil Stabilized with Fly Ash as Lightweight Fill Materials for Embankment Construction

Abstract

Design and construction of road embankment presents several challenges, including the possibility of bearing capacity failure, large total settlement, differential settlement, and slope instability, which may result from the weight of the embankment construction itself, and/or weak foundation. A number of techniques have been developed and can be used to overcome these problems, one of them is by modifying the weight of the embankment itself with the use of lightweight materials, such as soil-EPS mixture. The use of soil-EPS mixture as lightweight material provides several advantages, among which can achieve the same volume or elevation requirement with a significantly lighter weight compared to ordinary materials, improving slope stability, embankment over high compressibility soil, and to reduce soil pressure to soil retaining structures, abutment or bridge pillar. Fly ash also added to act as binder to increase shear strength of mixture. The result of the compaction test shows that the addition of a small amount of EPS to the mixture can significantly reduce the maximum dry density of the mixture. Triaxial UU and UCS test results show a reduction in mixture strength as EPS contents increase, but due to the presence of fly ash increases the strength of mixture as the number of day increases, so that the use of lightweight materials has the potential to be one of soil improvement solutions.