CHAPTER 1

INTRODUCTION

1.1          
General

For centuries people were
wondering at the instability of earth materials particularly like expansive
soil, sometimes dry and hard, and the other time wet and soft. Common cause of foundation problems which
is expansion of soil is also heard as shrink-swell soil. Shrink-swell soils
will participate changes in volume of up to thirty percent or more depends on
the supply of moisture in the ground. Foundation soils which are pricy will
“haul” and can affect the lifting of a building construction or other structure
during periods of high moisture. Conversely during periods of falling soil
moisture, expansive soil will “collapse” and can result in building settlement.
Either way, damage can be extensive. Even when efforts are made for the purpose
of improving swelling soil, the lack of applicable technology usually results
volumetrically change which cause billions dollars damage every year. This is
due to the present of work is taken. The aims were to examine the scope improving
hearing capacity of the soil and reduce expansiveness by adding additives. Many
additives for soil modification such as Ordinary Portland Cement, fly ash and
lime ash.

In thermal station, coal is used as the primary
fuel. The addition to stabilize the soil from this stations is collected and it
is called fly ash and it is observed as waste material. Fly ash is distributed in
the dry form or mixed with water and release in slurry into locations recognize
as ash ponds. The fly ash is demand and increase by quantity in many country.
China, India, United States, and Poland alone produce about 270 million tons in
fly ash er year. (Mattheus F.A Goosen, 2006) (Amir Ali Al-Rawas, 2006) (Mustafa
Yaykiran, 2008). The example of typical damage of expansive soil are shown in
figure 1.1 and figure 1.2 below;

Figure 1.1 Effects of expansive soil

Figure 1.2 Damaged by expansive clay soils

1.2          
Statement Of The Problem

       The
issues of expansive soil are more noticeable than other issues that have
happened. Few problems of expansion soil do not show up in the actual time. Besides,
due to rainy seasons, cracks begin to develop with association of accumulation
of leaking water from the domestic use. Because of that, the destruction will occur
in few years. The foundation that used to hold up the superstructures such as
isolated pads, short columns and ground beam must be a ductile structure also
with the walls that were manufactured of concrete blocks. As a result of
expansive soil, it was found that upward movement caused the ductile
substructure foundation to twist and also bring dangerous harm to the brick
wall and several concrete structural members such as ground beam and grade
slab.

1.3          
Research
Objective

·       To
determine the physical properties of expansion soil.

·       To
determine the shear strength properties of expansion soil.

·       To
evaluate the effects of fly ash addition on the strength of the expansive soil.

1.4          
Scope
Of Study

The scope of study is to
improve the strengths of the expansive soil that may occur at the construction
site. The location to collect the sample will be in Selangor area which will be
decided by individual investigators. The substance that will be used to treat
the expansive soil in this situation is fly ash. Three different percentage of
fly ash which are 10%, 20%, and 30%, will be used to investigate and analyse
the strengths of the soil in this experimental works. The lab tests will be
held at IKRAM labs.

1.5          
Significant
Of Study

The
foundation engineers may face one of the common problems in soil which will be
the soil expansion. Various efforts are being implement to control the
swell-shrink performance of these soils. Chemical substance are the most
functional and low cost strategies used. The products of coal burning thermal
power plants which is fly ash, is increasing in large quantities in the whole
world and considered as major environmental matter. The objective of this
project is to provide a study regarding the support of rigid structure which
can reach the expansive ground subsurface. Possible swelling of expansive soil
is calculated with few percentage values of fly ash. Expansive soil that
contain the fly ash and not are compared based on the index properties for
example the plastic limit, liquid limit and shrinkage limit.