CHAPTER 2
LITERATURE REVIEW
2.1
Introduction
The in-situ density of natural soil is needed for the determination of bearing
capacity of soils, for the purpose of stability analysis of slopes, for the determination
of pressure on underlying strata for the calculation of settlement and the design of
underground structure. It is very quality control test, where compaction is required, in
the cases like embankment and pavement construction.
2.2
Origin, Formation, And Distribution Of Soils
Geologic and physiographic data can be used to great advantage in considering
the engineering properties of soils on a continental basis. Geologic information aids
in categorizing soil materials on the basis of parent materials and/ or methods of
transportation.
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Soil may be divided into two broad classes on the basis of origin:
(1) residual - those derived in place from bedrock, and (2) transported - those
deposited by wind, water and ice. Both classes vary through a wide range of large
distances, mostly by water flowing in creeks and rivers. Much of the sand, gravel
and clay eventually settle in riverine floodplains; sand is also deposited in coastal
dunes and estuaries and offshore deposits.
Sand, particles from 2 mm to 0.06mm, is subdivisions into coarse, medium
and fine. Sand has a gritty feel, and shows very little or no cohesion when dry. Sand,
whether it is found on beaches or in rivers and stream, is mostly quartz (silicon
dioxide, SiO2) grain. For some applications, it is the silica content (quartz) of the sand
that makes it so valuable. The sand and gravel deposits that have proven to be most
valuable are from present and ancient river channels, river flood plains and glacial
deposits.
2.2.1
Sadong Formation
The Sadong Formation is composed mainly of moderately to steeply folded
feldspathic sandstone, shale, and arkose, with minor amounts of conglomerate,
limestone, chert and tuff. The predominantly arkosic sediments are termed the Serin
Arkose Member. The formation is underlain by the Upper Carboniferous to lower
Permain Terbat Formation, and is overlain unconformably by the Kedadom
Formation and by the Upper Jurassic Part of the Bau Limestone Formation. The
Sadong Formation contains lamellibranchs of Upper Triassic (Carnian to Norian) age.
(G. E. Wilford, 1965)
The rocks described here as Sadong Formation were first mapped by Krekeler
(1932, 1933) and Krol (1930). The Sadong Formation, formally introduced in 1960
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by Haile (Liechti et al., 1960 p.31) to describe the sedimentary rocks of Triassic age.
This terminology is used here, the arkosic sediments of the formation being separately
defined as the Serin Arkose Member.
The type area of the Sadong Formation is the Sadong and Kedup Valleys near
Serian, immediately east of the Penrissen area (Pimm, 1965). The type area of the
Serin Arkose Member is the Serin Valley below Setebut and the area immediately to
the west, in the Penrissen area. The Sadong Formation underlies 59 square miles of
mainly low-lying country in the north and east of the Penrissen area.
Characteristically, the sandstone-shale facies of the Sadong Formation forms
small hills with straight to slightly concave slopes and sharp ridge summits. Soils
developed on the sandstone-shale facies are commonly buff, cream, or pale yellowish
brown in contrast to the predominantly reddish to orange-brown colours of soil
developed on arkose.
The Sadong Formation is composed of feldspathic sandstone, sandy shale,
shale, and arkose with subordinate conglomerate, limestone, chert, and a few
predominantly intermediate to acid pyroclastic rocks. Sandstone is the dominant rock
type and occurs as beds averaging 10 to 20 feet and occasionally as much as 100 feet
thick. Shale and sandy shale are usually sheared and occur as layers of a few feet thick
between the sandstone beds; some shale layers however are as much as 50 feet thick.
2.2.2
Silica Sand
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Most dissolved silica enters modern oceans via riverine imput derived from
the weathering of silicate rocks, with about 10% of the riverine imput removed in
estuarier (Treguer et al 1995). Submarine hydrothermal sources and sea-floor
weathering may account for about 10% of overall dissolved silica imput, and the
dissolution of eolian
dust may supply an additional 8% of the imput. Today the removal of marine silica is
controlled by diatoms, with greater than 80% of the burial in abyssal regions and most
of the remainder accumulating on shelves (Treguer et al 1995). The extent of biogenic
recycling of silica is illustrated by the fact that about 40 times the annual dissolved
silica imput is biogenically removed, keeping ocean water under-saturated with
respect to silica.
Silicate weathering is commonly interpreted to remove CO2 from Earth’s
atmosphere and favors an icehouse world if a sufficient amount of that C can be buried
(Walker et al 1981; Worsley & Nance 1989; Barner 1990). The volume of silicate
rock affected by weathering may be increased due to factors such as (1) uplift of
mountain ranges that expose fresh silicate rock (Chamberlin 1899; Raymo 1991), (2)
expansions of land plants that deepen the extent of surface weathering (Berner 1997),
including increased development of roots systems (Drever 1994; Algeo et al. 1995;
Algeo and Scheckler 1998) and (3) increased exposere of silicate rocks when relative
sea level is lowered (Worsley and Kidder 1991; Worsley et al. 1994). Positioning of
land masses at low latitudes may lead to increased levels of silicate weathering
(Walker et al. 1981; Worsley and Kidder 1991). If the magnitude of silicate
weathering is substantial enough to stimulate climate change, it should also
significantly increase the mass of dissolved silica input to the oceans.
It is important to recognize some fundamental differences between the silica
sand and construction sand industries. In common with all minerals, silica can be
extracted only where mineral occurs. ‘Silica Sand’ (also known as ‘Industrial Sand’)
is sand which contains a high proportion of silica in the form of quartz and is market
for purposes other than for direct use in the construction industry. It is important that
an adequate supply of silica sand is maintained from all sources. High quality silica
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sands are scarce. The working of minerals has environmental implications for
communities and landscapes and this must be carefully balanced against the need for
the mineral. It is produced from both unconsolidated sand and crush sandstone, with
processing to marketable form being of varying degrees of complexity depending on
end-use. The mount of construction sand as a proportion of total production from a
site varies greatly and will depend on several factors including the geology of the
deposit.
Foundry sand is high quality silica sand that is a by- product from the
production of both ferrous and nonferrous metal castings. The raw sand is normally of
a higher quality than the typical bank run or natural sands used in fill construction sites.
Foundry sand is basically fine aggregate. It can be used in many of the same ways as
natural or manufactured sands. This includes many civil engineering applications
such as embankments, floeable fill, hot mix asphalt (HMA) and portland cement
concrete (PCC). The largest volume of foundry sand is used in geotechnical
applications, such as embankments, site development fills and road bases. The quality
of foundry sand can be quantified by it durability and soundness, chemical
composition and variability. The compactness of using foundry sand will increase for
the foundries and for the end users of the sand.
2.2.3
The River Sand
The river sand at Batang Sadong is composed of the bulk of the sandstone
deposition. The sandstone is thick-bedded to massive, commonly cross-bedded,
moderately well-jointed, pale-grey, speckled with dark-grey and black, medium- to
coarse-grained, and composed essentially of sub-angular quartz, feldspar,
metamorphic rock fragments, and chert. Quartz grains comprise from 50 to 85
percent of the coarser grained sandstone. Heavy minerals in the sandstone include
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apatite, zircon, and possibly tourmaline. The matrix of the sandstone, typically scanty
in the coarser grained rocks, is mainly sericite with some chloride, and quartz or
calcite.
The river sand is normally used as filling material for road construction project.
However, it is also used as part of the concrete material.
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2.3
The Role Of Testing
The conducting of physical tests on materials and workmanship is a most
essential part of the quality control regime required to be applied by the supervision
team and from a management point of view needs to be regarded as integral with the
inspection and approval site procedures.
2.3.1
Density
The definitions for ‘density’:
1)
The quality of being compact or dense.
2)
The quality of matter in a given space based on the ratio of mass to
volume.
The mass of unit total volume of a particulate solid is described as its density,
or bulk density. It is presented in the form of equation:

m
V
2.1
Where,
 is the density
m is the mass
V is the volume
The process of mechanically pressing together the particles of a soil to increase
the density (compaction) is extensively employed in the construction of embankments
and in strengthening the subgrade of roads and runways. The density achieved by
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compaction is invariably expressed as dry density, generally in Mg/m3 although,
occasionally, the unit kg/m3 is used.
2.3.2
In Situ Density Test
The in situ density of natural soil is needed for the determination of bearing
capacity of soils, for the purpose of stability analysis of slopes, for the determination
of pressures on underlying strata for the calculation of settlement and the design of
underground structures.
The material tested in situ by a field test is analogous to a laboratory sample,
and can be considered as a ‘field sample’. The in situ conditions of a field sample may
be affected by the process of gaining access to the position, e.g. digging a trial pit.
In essence, most of the available methods of field density test methods depend
upon the removal of a representative sample of soil from the site and then determining
its mass and the volume it occupied before being removed. Mass determination is
common to all methods and is straightforward. The variations lie in the several
procedures used for measuring the volume and these depend upon the nature of the
soil being tested.

The dry density achieved in the field after compaction must be compared with
the maximum value obtained in the laboratory. The required quality standard may be
specified in terms of the relative compaction percentage.
Rc 
Where,
ach  100
d max
2.2
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Rc is the relative density
ρdach is the dry density achieved
ρdmax is the maximum dry density
In order to measure the achieved field dry density, frequent measurements of
bulk density and moisture content of the placed material are necessary.
There are few methods of test are in general use. All methods require physical
access to the soil in situ, and are therefore normally restricted to soil within 2 m or so
of the surface, although, of course, they can equally well be used in deep shafts or
headings.
2.3.3
The Test Methods
1)
The sand replacement method:
By conducting this test it is possible to determine the field density of the soil.
The moisture content is likely to vary from time and hence the field density also. So it
is required to report the test result in terms of dry density. The relationship that can be
established between the dry density with known moisture content is as follows:
d 
b
100  w
Where,
ρd is the Dry density
 2.3
2.3
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ρb is the Bulk density
w is the Moisture content
This method is suitable for granular soils and involves the use of a
sand-pouring cylinder. Firstly, a small hole is dug about 100 mm in diameter and not
more than 150mm in depth and the soil removed carefully weighed. The volume of
the hole is then determined by pouring sand into it from the pouring cylinder. The
sand-pouring cylinder is weighed before and after this operation, and the mass of sand
filling the hole determined. Since the density of the sand is known, the volume of the
hole can be determined, and hence the bulk density of the in-situ soil. Two sizes of
sand-pouring cylinder are recommended: a small version suitable for fine- and
medium-grained soils and a large version for fine-, medium- and coarse-grained soils.
Photo 2.1 is the sand-pouring cylinder and Figure 2.1 is the sand pouring cylinder
sketch.
Photo 2.1: Field Density Test Equipments
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Figure 2.1: Sand Pouring Cylinder Sketch
2)
The core cutter method:
The method depends on upon being able to drive a cylindrical cutter into the
soil without significant change of density and to retain the sample inside it so that the
known internal volume of the cylinder is completely filled. It is therefore restricted to
fine soils that are sufficiently cohesive for the sample not to fall out, and to chalk soils
or completely weathered rock free of stones. The method is generally less accurate
than the sand replacement method because driving the sampler tends to alter density of
the soil.
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3)
Weight in water method:
It is applicable to any soil where representative samples occur in discrete
lumps which will not disintegrate during handling and submersion in water. In
practice the method is restricted mainly to cohesive soils.
4)
Rubber balloon method:
In essence it is a water replacement test with a rubber membrane retaining the
water. It is an alternative to the sand replacement method with the limitation that it is
not suitable for very soft soil which will deform under slight pressure or in which the
volume of the hole cannot be maintained constant.
5)
Water displacement method:
The water displacement method is an alternative to the weight in water method
and has the sand limitations.
6)
Nuclear methods:
They do not measure density directly, and calibration curves have to be
established for each soil type, which involves measuring the densities of
representative samples of the soils concerned by conventional methods. However,
once this has been done and provided there are no significant changes in soil type, the
method is very much faster than the others. The equipment utilizes radioactive
materials, and appropriate safety precautions should be taken. Because of its
limitations, the method is little used in the United Kingdom.
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2.4
General Description Of The Site
Batu Kitang road project involves the improvement and sealing of the existing
Bau Road, Kuching Division.
The section of the existing road commences from the existing Batu Kitang
road toward Kota Sentosa direction. It is involving a 1.5 kilometres length of road.
The scope of works including surveying and setting, general site clearing and
grubbing, stripping topsoil, disposal of material, general earthwork operations,
drainage works, road pavement work including supply and construct subgrade,
subbase, roadbase, asphaltic concrete wearing and binder course and to carry out
laboratory tests and in-situ testing as specified.
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