Publication: Determination of the ultimate load of encased stone column
Date
2015
Authors
Nik Ab Aziz N.N.S.
Hafez Jaheen M.A.
Mukri M.
Abdul Ghani A.H.
Khalid N.
Journal Title
Journal ISSN
Volume Title
Publisher
E-Journal of Geotechnical Engineering
Abstract
The main purpose for this study is to determine the ultimate load of encased stone column. As we know, clay is a soil that is very soft and usually need a treatment before construct any structure on it. Besides that, it also has a high moisture content compare to other types of soil. Many contractors are not confident enough to use stabilization methods such as mechanical method to treat this kind of soil. For this study, the soil that is used is kaolin soils which are one of the types of clay soil. Other than that, the main material to form the stone column is gravel and is also provided in soil laboratory. The material that is used to encase the stone column is woven geotextile. The geotextile is taken from Tencate Geosynthetics Sdn. Bhd. The laboratory test is conducted to the kaolin and gravel in order to know the physical and engineering properties of this material. Then, shear box test is done in different condition in order to know the friction angle, cohesion and interface shear strength of the material. Forty five numbers of samples are prepared which 9 of them are not being tested with geotextile. Meanwhile, the other 36 samples of the sample are tested using different tensile strength of geotextile. From the shear box test, it is found that the geotextile with high tensile strength give higher value of shear strength. So, this geotextile is chosen to encase the stone column. Then, the soil sample is prepared in a large consolidometer cell. This soil is consoled with 5 kPa of preloading before installation of stone column. During this stage, the settlement value is recorded After consolidation process is done, the stone column with 100 mm in diameter and 450 mm length is formed. Then, once again the soil with stone column is preload with 5 kPa and the settlement also is recorded. It is found that the settlement value before and after installation of encased stone column is quite different. The settlement value before installation of stone column is 25 mm for 25 days and reduced to 15 mm after installation of stone column. Last but not least, the plate load test is carried out to the column in order to know the ultimate bearing capacity of the column. In a nutshell it is prove that, encased stone column method can be used to treat soft soil because it can reduce about 40% of settlement and can increase the strength of the soil. � 2015 ejge.
Description
Clay; Geosynthetic materials; Geotextiles; Gravel; Interfaces (materials); Kaolin; Soil mechanics; Soils; Stability; Stabilization; Tensile strength; Engineering properties; High moisture contents; Interface shear strength; Soft soils; Soil stabilization; Stone column; Ultimate bearing capacity; Ultimate loads; Soil testing; bearing capacity; clay soil; column; geotextile; loading; moisture content; shear strength; shear test; soil stabilization; soil-structure interaction