Compressibility Characteristics of Fibrous Tropical Peat ... - Ejge.com

Vol. 14, Bund. C 6
Testing programs
The samples were from marine and continental deposits of the Kampung Jawa Klang, Selangor,
west coast of the Malaysian peninsula. They consisted primarily of fibrous organic soils and some
fine-to-medium sands and were dark brown in color.
As mentioned earlier, this study prepared the samples in accordance with BS 1377-1 (1990). We
determined such physical properties of natural soil used in the tests as organic content, water
content, liquid limit, and specific gravity in accordance with BS 1377-3(4) (1990), BS 1377-2(3)
(1990), BS 1377-2(4.3) (1990), and BS 1377-2(8.4) (1990), respectively. We determined the
organic matter (content) of the peat samples based on test procedures according to ASTM D
2974-87, and used the Von Post scale to find the degree of humification (Huat, 2004). Sample
was then tested using Rowe Cell to overcome most of the disadvantages of the conventional
oedometer apparatus when performing consolidation tests on low permeability soils, including
non uniform deposits. The most important features are the ability to control drainage and to
measure pore water pressure during the course of consolidation tests (Duraisamy et al., 2007-a,
2007-b).
Figure 5: Rowe Cell Consolidation test set up used in this study.
The system was comprised of a Rowe Cell Consolidation, gradually diverging system (GDS)
pressure and volume controllers (Figure 5), and GDS laboratory software. The hydraulic loading
system pressure and vertical loads (50, 100, 200 and 300kPa) can be applied to the sample surface
either via a flexible diaphragm to give a uniformly distributed pressure (free strain) or via a rigid
plate to give uniform settlement (equal strain). The bottom drain is provided with a tapping to a
pressure transducer.
This study performed the consolidation tests on low permeability soils on the peat based on BS
1377-6 1990 and determined the compressibility parameters of the samples without having to remove
them from their sampling tubes. The samples therefore didn’t suffer disturbance due to
their preparation, and the moisture content of the soils at the respective test horizons could be
reported.
The compressibility parameters in soils which were tested to assess the effect of the cement
column with different cement ratio, to the consolidation parameters of the peat in this study are:
1. Coefficient of consolidation (C v ) 2. Compression index (C c ) 3. Coefficient of secondary compression
(C α ), and 4. Coefficient of volume compressibility (m v ).