THE UNDRAINED SHEAR STRENGTH OF SOFT CLAY REINFORCED WITH GROUP ENCAPSULATED LIME BOTTOM ASH COLUMNS

Abstract

This research was aimed to investigate the role of group encapsulated lime bottom ash columns
in improving the shear strength by using laboratory scale model. Kaolin was being used as soil sample and
lime bottom ash as the reinforced columns. The reinforced kaolin samples were tested by using Unconfined
Compression Test (UCT). A total 7 batches of kaolin sample had been tested and each batch consist of 3
specimens represent sample without lime bottom ash column, partially penetration and fully penetration for
group lime bottom ash columns. The specimen used was 50 mm in diameter and 100 mm in height. The height
of the group columns was 60 mm, 80 mm and 100 mm with 10 mm and 16 mm column diameter. The group
encapsulated lime bottom ash columns was installed in the triangular pattern, as it was much easier to maintain
the location of installed columns and the spacing in between the columns. The improvement of shear strength
of group encapsulated lime bottom ash columns with area replacement ratio of 12.00 % (10 mm column
diameter) and 30.72 % (16 mm column diameter) was 29.00 %, 44.17 %, 29.75 % and 1.00 %, 3.92 %, 7.33 %
at sample penetration ratio, Hc/Hs of 0.6, 0.8 and 1.0 respectively. It can be concluded that the shear strength
of soft clay could be improved by the installation of group encapsulated lime bottom ash columns. However,
the improvement of shear strength of 10 mm group encapsulated lime bottom ash columns was increased more
significant compared to 16 mm group encapsulated lime bottom ash columns.