Page 12 - CSEB Report

Study on Compressed Stabilized Earth Blocks

Sample 2 (Bjemina)
The liquid limit and plastic limit of the soil were 24.2% and 21.20% respectively. The
plasticity index of the soil was 3 and thus, the soil sample collected from Bjemina
construction site was classified as Sandy Silt of low plasticity.

Sample 3 (Debsi)
The liquid limit and plastic limit of the soil were 20.8% and 16.95% respectively. The
plasticity index of the soil was 3.85

Corresponding plasticity index of 3.85 and liquid limit of 20.80 % , the soil collected from
Debsi site was categorized as Sandy Silt of low plasticity

3.1.2.1 Discussion on soil test

Atterberg limit test by the Casagrande method was performed in accordance with [7] to
ascertain plasticity index (PI) of the soil samples. The results were presented in Table 1.
The PI of 0, 3, 3.85 for the sample I, sample II, and sample III are very low plasticity. Thus,
the soil could be either of the following types

1. Silty soil

2. In case of zero PI value, soil are considered to have little/no clay or silt and called non
plastic soil.

3. A lower plasticity index of soil is indicative to have high organic matter in soil.

Since the soil samples were collected from beneath the surface, after removing the top
black soil, most probably the soil is going to be sandy silt. Thus, indicating a suitable soil
for cement stabilization as their PI values does not significantly exceed 15% as stipulated
by [10].

3.1.3 Optimum moisture content (OMC)

The OMC serves as a guide for adding water during preparation and mixing of the block
units. The Moisture contents affects strength development and durability of the material
and hence have a significant impact in the long term performance of stabilized soil
material especially in bonding mortars at the time of construction. Different types of
compaction have influence on the optimum water content in the stabilized mixes. As

reported in [12], the optimum moisture content range between 10 to 13%

4. Compressed Stabilized Earth Block (CSEB)

The bricks made of a soil and the stabilizer upon certain pressure with optimum water
content in a mold is known as Compressed Stabilized Earth Blocks (CSEB). The bricks are

molded using Auram press 3000 and CINVA-Ram machine which is a hand operated press
for block making.

11 Engineering Adaptation and Risk Reduction Division (EARRD), DES, MOWHS