report open ended baru

60
CHAPTER 1 INTRODUCTION 1.1 INRODUCTION The term settlement refers to the vertical downward displacement at the base of a foundation or other structure due to the ground movement. There are several mechanism which may produce ground movement, and there are many types of structure, with varying potentials to withstand or to be distressed by movement. Brick and masonry building are brittle and may sustain crack and even structural damage following very small foundation displacement, other structure may be constructed to sustain considerable movement without suffering real damage. Also, soil conditions are keep to change, often considerably, from before, to during, and also after construction. Most building damage occurs when unforeseen soil condition arise, inadequate site investigations and a lack of understanding of soil behavior are largely to blame. Method are available by which both the amount and the rate of foundation settlement can be estimated. These estimate will remain reasonably reliable providing that the assume soil condition 1

Upload: ir-fik-t

Post on 28-Sep-2015

10 views

Category:

Documents


0 download

DESCRIPTION

abc

TRANSCRIPT

CHAPTER 1INTRODUCTION

1.1 INRODUCTION

The term settlement refers to the vertical downward displacement at the base of a foundation or other structure due to the ground movement. There are several mechanism which may produce ground movement, and there are many types of structure, with varying potentials to withstand or to be distressed by movement. Brick and masonry building are brittle and may sustain crack and even structural damage following very small foundation displacement, other structure may be constructed to sustain considerable movement without suffering real damage.Also, soil conditions are keep to change, often considerably, from before, to during, and also after construction. Most building damage occurs when unforeseen soil condition arise, inadequate site investigations and a lack of understanding of soil behavior are largely to blame. Method are available by which both the amount and the rate of foundation settlement can be estimated. These estimate will remain reasonably reliable providing that the assume soil condition represent the actual condition and are likely to persist throughout the life of the building.The soil around the Murni Apartment is one of several places in Universiti Tenaga Nasional (UNITEN) that we taked as the sample. The non-drained shear strength of this area will be determined by in-situ testing method and the result will show that whether treatment of soil is need to be done when a structure is intend to be built. The site investigation data and analysis will be done and taken as well as the sampling procedures. The soil sample will be tested in laboratory to obtain its basic engineering properties and shear strength. All the data will be used in order to obtain valuable information of the sand.

1.2PROBLEM STATEMENTStructures are mean to stand firm for many years to come and more importantly, could provide great strength to support loads within the structure. Consolidation settlement was a major topic discussed by the civil engineers and geologist particularly when dealing with structure design involving foundation. The predictions of long term settlement can be determined by the soil exploration. In this study the prediction of the settlement for highway construction project have been selected and discussed as a case study. Depending on the soil type, a foundation soil for highways construction maybe prone to large and rapid settlement due to consolidation behavior in laboratory in order to portray the actual soil condition. The soil sample were investigated in a laboratory by consolidation test which was done by using the odometer apparatus. Finally, the consolidation time and settlement can be predict from the odometer result.

1.3PROPOSED SOLUTIONConsolidation settlement was a major topic discussed by the civil engineers and geologist when designing the structure. From past, many case of building problem and failure found that settlement could affect them by continuing settlement for many years with total accumulated settlement being very large. This settlement may due to creep or secondary settlement. There are many method used to predict the settlement such as Casagrande Odometer (Terzaghi 1923 ; Casagrande 1936). We can predict the primary and secondary settlement in laboratory using consolidation odometer test. The reliability of the prediction depend on many factors such as good sample, human, apparatus, and other uncertainties soils.

1.4AIM AND OBJECTIVE

The main reason of the project is :I. To determine and identify the type of soil sampled from site through basic soil classification testII. To justify the selected site for soil sampling.III. To differentiate between disturbed and undisturbed soil samples obtained from site for different types of laboratory soil testingIV. To evaluate the soil rate of consolidation and predict consolidation settlement of the soil at site.

1.5SCOPE OF WORKThe main scope of this project is to determine the coefficient of consolidation (cv) of soil sample. The scope of study has been narrowed down so the study will not exceed the limit stated. The scope of work involved in this study is in-situ soil testing. The main testing is involving the specific gravity, sieve analysis, and consolidation test. For plastic limit and liquid limit is just as one options . The testing method will be done only in the laboratory which means there is no field testing involve.

CHAPTER 2LITERATURE REVIEW

2.1SOIL CLASSIFICATION PRINCIPLEIt is necessary to provide a conventional classification of type of soil for the purpose of describing the various materials encountered in site exploration. The system adopted need to be sufficiently comprehensive to include all but the rarest of natural deposit, while still being reasonable, systematic and concise. Such a system is required if useful conclusion are to be drawn from the knowledge of the type of materials. Without the use of a classification system, published information or recommendations on design and construction based on the type of the material are likely to be misleading and it will be difficult to apply experience gained to future design. Furthermore unless a system of conventional nomenclature is adopted, conflicting interpretation of the term used may lead to confusion, rendering the process of communication ineffective.Most classification system divide soil into three main groups: course, fine and organic. The main characteristic differences displayed by these group are shown in FigureFigure 2.1: Major classes of engineering soils

The range of particles size encountered in soil is very wide: from around 200mm down to the colloidal size of some clays of less than 0.001mm.Although natural soils are mixture of various sized particle, it is common to fine a predominance occurring within a relatively narrow band of sizes. When the width of this size band is very narrow the soil will be term poorly-graded, if it is wide the soil is said to be well graded. A number of engineering properties, e.g permeability, frost susceptibility, compressibility, are related directly or in directly to particles size characteristic.Figure 2.2 shows the British Standard range of the particles size. The particles size analysis of a soil is carried out by determining the weight percentages falling within bands of size represented by divisions and subdivision. In the case of a course soil, from which fine grained particles have been removed or were absent, the usual process is a sieve analysis. A representative sample of the soil is spilt systematically down to be convenient sub sample size and then oven dried .This sample is then passed through a nest of standard test sieve arranged in descending order of mesh size. Following agitation of first the whole nest and then individuals sieves, the weight of the soil retained on each sieve is determined and the cumulative percentages of the sub sample weight passing each sieve calculated.

Figure 2.2 : British Standard Range of Particle

For our sample we has determined that our sample is catagorised as a WELL GRADED/POORLY GRADED SILTY SAND. In that case proceed to next testing which is specific gravity and odometer test. But in this study we also do the Plastic and Liquid limit as a options.

2.2SPECIFIC GRAVITY OF SOILThe specific gravity of a material is defined as the ratio of the mass of a unit volume of a material to the mass density of gas-free distilled water at a stated temperature. Specific gravity of soil solids is written as Gs = s / w (1) where s and w are the mass density, mass per unit volume, of the soil solids and water, respectively. A material with a specific gravity greater than water is denser than water so it will not float in water. Specific gravity is used in computations involving phase relationships that are expressed in terms of unit weight, where unit weight is defined as the weight of material per unit volume. The specific gravity of soil solids falls within the following ranges of values.

Gs = Ms/Vs w

=

Gs = specific gravity of soilMs= mass of solid ,gVs = volume of solid,cm w = density of water (1 g/cm)

Let, in the figure * The value of specific gravity depends on the temperature

M1 = Mass of empty density bottle.M2 = Mass of density bottle + Soil grains.M3 = Mass of empty density bottle + Soil grains + water.M4 = Mass of empty density bottle + water.

2.3LIQUID LIMIT In the early 1990s, a Swedish scientist named Atterberg developed a method to describe the consistency of fine-grained soils with varying moisture contents. Atterberg limits are defined as the water corresponding to different behaviour conditions of fine-grained soil (silts and clays). The four states of consistency in Atterberg limits are liquid, plastic, semisolid and solid. The dividing line between liquid and plastic states is the liquid limit; the dividing line between plastic and semisolid states is the shrinkage limit. If a soil in the liquid state is gradually dried out, it wills past through the liquid limit, plastic state, plastic limit, semisolid state and shrinkage limit and reach the solid stage. The liquid, plastic and shrinkage limits are therefore quantified in terms of the water content at which a soil changes from the liquid to the plastic state. The difference between the liquid limit and plastic limit is the plasticity index. Because the liquid limit and plastic limit are the two most commonly used Atterberg limits, the following discussion is limited to the test procedures and calculation for these two laboratory tests.The liquid limit is that moisture content at which a soil changes from the liquid state to the plastic state. It along with the plastic limit provides a means of soil classification as well as being useful in determining other soil properties.As explained, plastic limit is the dividing line between the plastic and semisolid states. From a physical standpoint, it is the water content at which the soil will begin to crumble when rolled in small threads.Liquid limit is significant to know the stress history and general properties of the soil met with construction. From the results of liquid limit the compression index may be estimated. The compression index value will help us in settlement analysis. If the natural moisture content of soil is closer to liquid limit, the soil can be considered as soft if the moisture content is lesser than liquids limit, the soil can be considered as soft if the moisture content is lesser than liquid limit. The soil is brittle and stiffer.The liquid limit is the moisture content at which the groove, formed by a standard tool into the sample of soil taken in the standard cup, closes for 10 mm on being given 25 blows in a standard manner. At this limit the soil possess low shear strength.2.4PLASTIC LIMIT Plastic limit test is conducted to determine the moisture at the point of transition from plastic to semisolid state. The plastic limit is defined as the minimum water content at which a soil will just begin to crumble when rolled into a thread of 3.2mm in diameter .Soil is used for making bricks , tiles , soil cement blocks in addition to its use as foundation for structures.The following moisture conditions liquid limit, plastic limit, along with shrinkage limit are referred to as the Atterberg Limit after the originator of the test procedure.

Figure 2.3 : Atterberg Limit & Indices.

2.5CONSOLIDATION TEST In saturated cohesive soil the effect of loading is to squeeze out pore water; this process is called consolidation. A gradual reduction in volume occurs until internal pore pressure equilibrium is reached. Unloading result is swelling, providing the soil can remain saturated. A detailed study of the consolidation process and methods of assessing the resulting settlement. The rate of the consolidation depend on the soil permeability can be very slow in fine soils, so that it may take several years for the final settlement to be achieved.When a saturated mass of soil is loaded, say by foundation, an immediate increase in pore pressure occurs and a hydraulic gradient is set up so that seepage flow take place into surrounding soil. This excess pore pressure dissipates as water drain from the soil: very quickly in coarse soil (sand and gravel), and very slowly in fine soil (silt and clay) which have low permeability. As water leaves the soil a change in volume accurs, the rate gradually diminishing until steady state condition are regained. The process is called consolidation.Terzaghi (1943) suggest the model of one- dimensional consolidation which used the steel spring technique that represents the soil. It is assumed that the frictionless piston was supported by the spring and the cylinder was filled with water. If a load was applied to the piston by the closed valve, the length of the spring will remain unchanged since the water was assume as incompressible. If the load was induced an increase in total stress of the whole of the consideration must be count initially by an equal increase in pore water pressure u.For standard references ASTM D 2435- Standard Test Method for One Dimensional Consolidation Properties of Soil.

Figure 2.4 : One dimensional consolidationa) Terzaghi model b) stress- time curve

Figure 2.5 : Section of a Typical Consolidation Cell

2.6THE DIFFERENCES BETWEEN DISTURBED AND UNDISTURBED SAMPLEGeotechnical engineers and geologists collect soil samples to learn about the properties of the strata below the land surface. To collect the samples, scientists often use drill rig or hand augers and special sample collection tools to gather both disturbed and undisturbed soil samples. The type of test that the geologist or engineer must run will dictate the sample collection method.

Undisturbed soil sampleUndisturbed soil samples keep the structural integrity of the in-situ soil and they have a higher recovery rate in the sampler. Its actually tough to gather a perfect undisturbed sample and the samplers may contain a small portion of undisturbed soil at the top as well as the bottom of the sample length. Undisturbed samples allow the engineer to identify the properties of strength, permeaility, compressibility, as well as the fracture patterns among others. Usually, the results of these analyses help many geotechnical engineering firms in terms of designing a new building.Drill rigs are usually used in collecting undisturbed soil samples at a depth and tools such as long split spoon samplers, pitcher barrel sampler, and piston samplers are required. A piston sampler is a thin-walled tube sampler that collects undisturbed samples in the soft soil. Piston samples dont work well in gravel, as well as in lithified sediments. Just like the piston sampler, a pitch barrel sampler is pushed towards the soil to collect the undisturbed sample. These techniques can produce the best undisturbed soil samples, therefore, an engineer who works in a certain geotechnical engineering company should remember to inspect the sample first if there are any sign that the soil sample was disturbed during collection or not.

Disturbed soil sampleIn Geotechnical Engineering, disturbed soil samples do not keep the in-situ properties of the soil when in the process of collection. Geotechnical engineers do not consider them to be representative of underground soils unless if theyre for tests that dont depend on the soil structure itself. Usually, scientists test the disturbed samples of soil for texture, soil type, moisture content, as well as the nutrient and contaminant analysis. Most of the soil samples that engineers and geologists collect are disturbed samples since theyre a lot easier to collect and the precision necessary for gathering an undisturbed sample isnt required for many soil tests.In collecting disturbed soil samples in Geotechnical Engineering, many methods are done. The essential methods include using a backhoe in creating a test pit where soil is collected from the bucket or by using hand augers to gather a sample from a vertical boring. You can also use drill rigs in collecting disturbed soil samples of great depths. Gathering disturbed samples of soil will need using collection tools such as Shelby tubes, split spoon samplers, and macrocore push samplers with the drill rig. It could even include the use of geotechnical engineering software.

Figure 2.5 : The disturb sample was taken

Based on the site, the experiment that been done are Sieve Analysis, Specific Gravity, Liquid Limit, Plastic Limit and Consolidation Test. Since that is difficult to collect the undisturbed sample, Consolidation test been done using a remolded sample of the disturb soil.

CHAPTER 3METHODOLOGY

3.1INTRODUCTIONIn this chapter, the techniques used in information and data gathering are being discussed. The datas are referred to facts and the consolidation value which is being studied and determined. All the facts and information gathered and compiled are strictly based upon the specific scope of which is mentioned in the literature review. In the mean time, the determination the coefficient of consolidation (cv) of soil is achieved through laboratory tests. Diagram 3.0 below is referring to the flow chart of this entire research.A specific site was chosen for the purpose of soil sampling. Hence, we decide to take the sample at behind Murni 3 parking area for the soil sample. A portion of about 10kg soil was taken back to the laboratory for further investigation. The soil sample was sieved using the sieve size of 2mm. Only a small portion of soil was needed for the sieving. The sieved soil was used for consolidation test. Diagram below is referring to the flow chart of this entire research.

THE SOIL WAS SIEVED BY SIEVE ANALYSIS TESTTHE UNWANTED MATERIAL WAS REMOVED10 KG OF SOIL WAS PREPAREDTHE SOIL WAS TAKEN BEHIND MURNI 3 PARKING AREASOIL SAMPLING

Determine theclassification of soil.

SPEIFIC GRAVITY TEST Choose the suitable test.

CONSOLIDATION TESTLIQUID LIMIT TESTPLASTIC LIMIT TEST

Determine the moisture content coefficient of consolidation

(OPTIONS)

3.2DESCRIPTION OF SOIL SAMPLING AT SITEThe site have been choose roughly due to several technical term and criteria such as topography and physical properties of soil for construction. From the soil sample that we took is to determine the soil type, soil classification and the settlement of the soil from a selected site. Soil that is to be taken will first examine based on its colour and texture. The colour of our soil at the site is dark and it is dried. This characteristics is enough to classify the type of soil that is needed to conduct the basic soil test.It was selected for the experiment sample test due to open ended based from a strategic area. This is easy for students to bring the sample to the lab. In addition, the soil still in good condition. It was not too disturbed because the land is nearby to the trees and no traffic areas.

Figure 3.1: Site Selection

Figure 3.2 : Sample have been taken by using spade

Figure 3.3 : Collecting sample into the tray

Figure 3.4 : Sieving process of soil sample to get in particles size 2-mm

3.3 EXPERIMENTAL PROCEDURE

3.3.1 SIEVE ANALYSISThe experiment was used the set of sieve size 5.00mm, 4.75mm, 3.35mm, 2mm, 1.18mm, 0.6mm, 0.425mm, 0.3mm, 0.15mm, 0.063mm, and pan to know the types of soil. A 200g of oven dried soil was obtain by weight it on electronic balance. Each sieve was cleaned and weight. All the sieve weight was recorded on the data sheet provided. The sieve pan was clean. After that, the sieve was placed in a stack of increasing aperture sizes. The largest sieve opening should be on top and the pan on the bottom.The soil sample was placed on the top sieve and the cover was placed tightly on the top. The sieve stack was placed into the sieve shaker. The sieve shaker was turn on. The sieve shaker was allowed to operate for 5 minutes. Once the sieve has stopped, the sieve stack was removed. Carefully disassemble the sieve stack. Be careful do not spill any of the soil. Each sieve was weight together with the soil retained and the pan also was weight plus the soil retained. All the weight was recorded on the data sheet.

Figure 3.5: Preparing the sieves with variety of size Figure 3.6 : Preparing the sample

Figure 3.7 : The sample was shake by using sieve shaker in 5 minutes

3.3.1SPECIFIC GRAVITYThe density bottle was cleaned and washed thoroughly with distilled water. After the density bottle was dried take the mass reading of empty bottle with its stopper accurately to 0.01g and marked as M1. After that 10 gram of oven-dried soil sample was added into the density bottle. The mass of the bottle M2 and its content with the stopper was found. The bottle was filled with distilled water so that the soil is fully soaked or full. The bottle was not filled completely, as the content was agitated under vacuum. The entrapped air was removed by subjecting the contents to a partial vacuum. The bottle was completely filled with deaired distilled water and was closed with stopper. The mass of the bottle and its contents, M3was determined. The bottle was kept empty and was cleaned thoroughly. The bottle was filled with deaired distilled water, a stopper was put on and the bottle was wiped dry from outside. The mass, M4 was found.

Figure 3.8 :The density bottle was dry and clean by distilled water

Figure 3.9 : Mass of density bottle, empty dish and dry soil was taken. Figure 3.10 : The dried soil sample was poured into density bottle.

Figure 3.11 :The bottle was filled of distilled water

3.3.2 LIQUID LIMIT TEST About roughly 300g of soil sample that passes sieve size 2.00mm had prepared. The height of fall of the liquid limit device was adjusted through which the cup is lifted and dropped where the point on the cup comes in contact with the base falls through exactly 10.00mm, the handle was rotated by one revolution. When the adjustment plate was complete, the adjustment was screwed tight. The soil sample was mixed thoroughly with distilled water on a large glass plate to formed uniform paste. A portion of the paste was taken with a spatula and placed it in the centre of the cup so that it is almost half filled.The surface of the wet soil was smoothed off level and parallel to the base maximum depth of the soil 10.0mm.Using the grooving tool, a clan, straight groove was cut through the soil dividing it into two halves, on a line joining the highest point to the lowest point on the rim of the cup. When the groove was cut, the tool must be held normal to the surface of the cup. The tip of the tool must scrape the bowl lightly. The handle of the apparatus had turned at the rate of 2 revolution per seconds to lift and drop the cup, until the two halves of the soil pat come in contact at the bottom of the groove along a distance of 12.7 mm. The number of blows required to close the groove was recorded.A slice of soil approximately the width of the spatula extending from one edge to the other edge of the soil cake at right angles to the groove including that portion of the groove in which the soil flowed together was collected, and put it in a weighted container and cover it. This was done to determine the water content of the soil sample.The remaining soil from the cup was removed and mixed it with the soil left on the glass plate. Add distilled water to increase the water content of the soil and decrease the number of blows required closing the groove.The steps were repeated successively and lower number of blows required to close the groove.

Figure 3.12 : Apparatus of liquid limit test

Figure 3.13 : Sample was mixed with distilled water

Figure 3.14 : Rotate 2 blows in to one seconds

Figure 3.15 : Make sure a sample touch to each other

Figure 3.16 : A little sample was taken to get a moisture content

3.3.2 PLASTIC LIMIT TEST A soil sample 50g of the material are taken and mix with water remaining from the liquid limit test. From that a ball were made and rolled on the glass of plate with the hand with just steady pressure at a rate of 80-90 strokes per minute. Therate of rolling may have to be decreased for very fragile soils.The mass was rolled into a thread of uniform diameter throughout its length until the thread reaches a diameter of approximately 3mm.At this point the thread began to act brittle and crumbled then the plastic limit was reached. The crumbled soil was collected in the airtight container and was kept for water content determination. The process was continued until the thread just crumble at 3mm diameter.

Figure 3.17 : Set of apparatus of plastic limit test

Figure 3.18 : Roll sample until the diameter 3mmthe soil begins to crack3.3.3CONSOLIDATION TESTThe specimen ring is weighed approximately 30mm of soil was extruded from the sample tube. The odometer cell- cutting ring was used as a guide template, the extruded soil sample was trimmed until the edged of the trimmed sample just allowing the cutter ring to slide over the soil. The ring is pressed down until it is centrally positioned with the upper and lower surfaces of the soil just protruding by an equal amount. A straight edge or spatula was used to trim these surfaces to be level with the end faces of the cutting ring. The specimen was weighted in the ring and the weight of the ring was deducted, to obtain the sample weight.

The moisture content of the sample is determined. After swinging the loading yoke clear of the centre line of the platen the filled cell was loaded .The loading beam was swing up to the vertical and the beam support is screwed to the point where it just touches the underside of the beam. the sliding arm attachment (where fitted) was set to the zero position. The beam was slowly lower and yoked until the screw spindle was just above the loading cap. If the beam, when contact was made above the horizontal, the support jack was raised to hold the lever arm and bring the screw spindle into contact by screwing down. Position was locked using the lock nut and the changed in the beam angle has a negligible effect on the loading ratio. The dial gauge was swing on its block and the spindle was above the top surface of the crossbeam screw spindle. a small positive reading is obtained after set the dial gauge, then the screw jack was ensured to support the beam, the first increment load was placed on the weight pan, then when ready to start readings, the screw jack was release and the timer is started.When a saturated soil mass was subjected to an increase in load, it is carried initially by increased pore water pressure. The resulting causes water to drain from the soil pores, shifting the load to the soil structure. The volume of the soil also decreases (equivalent to the volume of water drained) causing settlement. The process is known as consolidation.Three important soil properties found using a consolidation test are: Thecoefficient of consolidation, Cv, obtained from deformation-time curve data and an equation. It indicates the rate of compression under a load increment. Thepre-consolidation stress,C'p, obtained graphically from a log stress-void ratio curve. It indicates the maximum past effective stress the soil has been subjected to. Thecompression index, Cc, also obtained graphically from the log stress-void ratio curve. It indicates the compressibility of the specimen.

Figure 3.19 : Preparing the apparatus

Figure 3.20 : Poured the distilled water to make it into a soil paste

Figure 3.21: Trim this surface to be level with the end faces of the cutting ring

Figure 3.22: The apparatus is ready set up. Make sure the sliding arm attachment is set to the zero position

CHAPTER 4RESULT AND ANALYSIS

4.1RESULT AND ANALYSIS

4.1.1 SPECIFIC GRAVITY OF SOILDetermination No.1

1. Density bottle number50ml

2. Mass of density bottle, M1(g) + stopper32.7 g

3. Mass of bottle + stopper + dry soil, M2 (g)44.6 g

4. Mass of bottle+ stopper+soil+water, M3 (g)89.6 g

5. Mass of bottle +stopper +water, M4 (g) 82.1 g

Specific gravity, Gs2.70

Table 4.1 : Data of soil specific gravity

Soil Type Range of GsSand 2.63 2.67 Silty Sand 2.67 2.70 Silts 2.65 2.70 Silty Clay 2.67 2.80 Clay 2.70 2.80 Organic Soil 1+ to 2.60

According with the type of soil is WELL GRADED/POORLY GRADED SILTY SAND.The value of Gs meet the range.

4.1.2SIEVE ANALYSIS Data And Observation :Total sample mass = 200 g

SIEVENUMSIEVESIZEWEIGHT OFSIEVE (BEFORE) (g)WEIGHT OFSIEVE(AFTER) (g)MASSRETAINED(gram)RETAINED%PASSING%

1)5.00508.7518.69.94.9595.05

2)4.75447.1454.57.43.793.5

3)3.35472.2484.812.66.385.05

4)2.00413.0463.550.525.2559.8

5)1.18355.5363.58455.8

6)0.6358.3382.724.412.243.6

7)0.425332.3343.110.85.438.2

8)0.3335.3358.222.911.4526.75

9)0.15317.4337.720.310.1516.6

10)0.063395.7417.521.810.95.7

Pan382.4390.07.63.81.9

Total196.298.11.9

Table 4.2 : Data of sieve analysis

Mass of sample after sieving = 196.2 gSoil loss = 200 g 196.2 g = 3.8 gCalculationExample of calculation for the sieve size 2.00 mm :Mass retained on the sieve = 390.0 g 382.4 g= 7.6 gMass passed the sieve = (98.1 /100)*200 = 196.2 gTotal sample mass= 200 gTotal percent passed the sieve = 98.1 %

Figure 4.3 : Percentage of soil

Based from the graph,The percentage of types of soil100%-60% = 40% (gravel)60%-6% = 54% (Sand)6% = (silt)

Soil groupSymbolRecommended name

Coarse soilsFines %

GRAVELGGW0 - 5Well-graded GRAVEL

GPu/GPg0 - 5Uniform/poorly-graded GRAVEL

G-FGWM/GWC5 - 15Well-graded silty/clayey GRAVEL

GPM/GPC5 - 15Poorly graded silty/clayey GRAVEL

GFGML, GMI...15 - 35Very silty GRAVEL [plasticity sub-group...]

GCL, GCI...15 - 35Very clayey GRAVEL [..symbols as below]

SANDSSW0 - 5Well-graded SAND

SPu/SPg0 - 5Uniform/poorly-graded SAND

S-FSWM/SWC5 - 15Well-graded silty/clayey SAND

GPM/GPC5 - 15Poorly graded silty/clayey SAND

SFSML, SMI...15 - 35Very silty SAND [plasticity sub-group...]

SCL, SCI...15 - 35Very clayey SAND [..symbols as below]

Fine soils>35% finesLiquid limit%

SILTMMGGravelly SILT

MSSandy SILT

ML, MI...[Plasticity subdivisions as for CLAY]

CLAYCCGGravelly CLAY

CSSandy CLAY

CL90CLAY of extremely high plasticity

Organic soilsO[Add letter 'O' to group symbol]

PeatPt[Soil predominantly fibrous and organic]

Table 4.4 : The recommended standard for soil classification is the British Soil Classification System, and this is detailed in BS 5930 Site Investigation. Its essential structure is as follows:

4.1.1LIQUID LIMIT TESTContainer number1234

Number of blows20291530

Mass of container + wet soil (g)17.018.129.924.1

Mass of container + dry soil (g)15.015.526.720.3

Mass of water (g)2.02.603.203.80

Mass of container (g)8.708.518.08.3

Mass of dry soil (g)6.37.08.712.0

Water content (%)31.7537.1536.7831.67

Table 4.5 : Result of Liquid Limit TestThe percent of moisture content of 25 blows is 33.30%

4.1.2PLASTIC LIMIT TESTDetermination No.123

Container number123

Mass of container + wet soil (g)9.79.59.0

Mass of container + dry soil (g)9.59.408.9

Mass of water (g)0.200.100.1

Mass of container (g)8.608.78.30

Mass dry soil (g)0.90.70.6

Water content (%)22.2214.2916.67

Table 4.6 : Result of Plastic Limit Test

The value of Plastic Limit is 17.72%The plasticity index:15.58%

From the plasticity chart and our results where liquid limit is 33.30% while plasticity index is 15.58 %, the soil sample is classified as clay . This chart was based on the British Standard System

Figure 4.7 : Plasticity Chart based on British Standard (shida nanti yg ni ko ganti msukkan pic yg ko trik tu tau) dan 1 lagi amik graph conso dlm report lama masukkn ye

4.1.3CONSOLIDATION TEST

Diameter of soil specimen=48mmHeight of soil specimen=18mmInitial water content=45.36 %Loading= 2kg1 unit of dial gage=0.02mm

Elapsed time ,t (minute)Dial gaugeCompressiont

0000

0.251.860.03720.500

11.790.03581.000

2.251.750.03501.500

41.700.03402.000

81.660.03322.828

161.600.03204.000

251.560.03125.000

361.530.03066.000

491.500.03007.000

641.480.02968.000

811.480.02969.000

1001.480.029610.00

Table 4.8 : Odometer test data

Determination no1

Mass of container (g)61.10

Mass of container + wet soil (g)134.00

Mass of wet soil (g)72.90

Mass of container + dry soil (g)111.25

Mass of dry soil (g)50.15

Water content (%)45.36

Table 4.8 : Soil Water Content Determination.

CHAPTER 5 DISCUSSION

5.1SPECIFIC GRAVITYi. The soil grains whose specific gravity is to be determined should be completely dry.ii. We should weigh the density bottle with the stopper it should have been dried thoroughly especially the inner side of the bottleiii. Inaccuracies in weighting and failure to eliminate the entrapped air are the main source of error. Both should be avoided by careful working.iv. If pycnometer is used, the cap of the pycnometer should be screwed up to the same mark for each test. v. The specific gravity should be calculated at a temperature of 27oC and reported to the nearest 0.01. If the room temperature is different from 27oC, the following correction should be done.

5.2SIEVE ANALYSISThe possibilities of making errors while experiment was being conducted are relatively high. These errors can be caused by the apparatus itself. The electronic balance used to weigh the soil might have error due surrounding environment. There might have strong wind which eventually can affect the reading. The electronic balance might as well not set to zero before the weighing process was done. Besides that, error can also caused by human error. Before the sieve is weigh, it is proper to clean and remove any remaining soil particles from it.Moreover, during the process when shifting the total soil into the arranged sieves, some soil might spill out. The same happens when failed to place each sieve and pan cover tightly before shakes it in the motorized sieve shaker. Apart from that, some dust or particles of soil might be left on the analytical balance causing additional mass added to the samples reading.All this error can affect the reading which gives a drastic change in results during calculations and also causing soil loss. Therefore, in order to avoid small errors, before begin the experiment make sure all the apparatus is in good condition and pay full attention from the beginning to the end of the experiment.

5.2LIQUID LIMIT Although we were able to obtain the results of the experiment, there were some errors that occurred or done by us whether it was unavoidable or unintentionally.Most of the errors were human error which was done by us due to our carelessness. During the mixing of the soil, we might have not mixed the paste uniformly causing different water content at different part of the paste. This will affect the reading later of the experiment. The paste that needed to be placed parallel to the cassagrande cup also might not have been executed well since we only estimate the placement causing the depth to be not uniform throughout the cup. The depth of the paste that should have been 10mm was only estimated to the nearest value because there were no proper tools to measure the depth. During the process of giving blow to the soil, the speed of rotation needs to be constantly 2 revolutions per second but due to human timing it might not be at that rate of speed thus causing the total number of blows to be inaccurate.The environment factor that was out of our control also contributes to the inaccurate result such as wind. The electronic balance is a highly sensitive device any movement of wind can cause the reading to not stabilize and thus causing us acquiring inaccurate readings. Also, wind and temperature surroundings can cause the change to the moisture content of the soil used in experiment because we used 4 samples. During intervals of each sample, the moisture content might have changed. Therefore, in order to avoid small errors, before begin the experiment make sure all the apparatus is in good condition and pay full attention from the beginning to the end of the experiment and use electronic balance that having plastic barrier5.4PLASTIC LIMITSeveral contributing factors have been identified as the following The technique of rolling the soil into a thread was wrong as it could not be rolled on the glass plate as advised in the procedure as it easily slipped. Thread size was only measured with ruler, thus threads with crumble diameter of slightly larger or smaller than 3mm would not have been detected.

In order to make the test much more accurate, certain preventive steps must be taken: Glass plate should be roughened up to increase friction as to prevent slippage, thus making it easier to roll the soil into an even thread. The size of thread at crumbling point should be measured with veneer calipers or by comparing it to a standard 3mm rod. The apparatus required for the experiment should be clean. All the readings should be noted carefully. Practical applications The value of liquid limit and plastic limit are used to classify fine grained soil. The values of liquid limit and plastic limits are used to calculate flow index, toughness index and plasticity index of the soil.

5.3CONSOLIDATION TESTThe coefficient of consolidation is the parameter used to describe the rate at which saturated clay or other soil undergoes consolidation, or compaction, when subjected to an increase in pressure. It is measure in square centimeters per second or square inches per minute.The coefficient of consolidation can be measured in a laboratory. The process involves measuring the change in height of a soil sample as it is loaded in increments. The coefficient of consolidation can be determined by plotting the change in height against the logarithm or square root of time.The coefficient of consolidation measures one-dimensional consolidation, or consolidation that occurs when soil experiences no lateral strain. This is acceptable for most practical problems, where it is acceptable to assume that seepage and strain occur only in the vertical direction.Consolidation is one of the most important behaviors of saturated fine-grained soils that needs to be understood for settlement analysis of these soils. The two most important aspects of laboratory consolidation tests are: (1) estimation of the compression index (Cc), used to predict total settlement of normally consolidated soils provided the void ratio versus log (effective stress) is linear.(2) the coefficient of consolidation (Cv), used to predict the rate of settlement in the range of primary consolidation. The recorded thickness changes during one of the load stages in an odometer test are used to evaluate the coefficient of consolidation (cv). The procedure involves plotting thickness changes (i.e. settlement) against a suitable function of time and then fitting to this the theoretical Tv: Ut curve. In this way known intercepts of Tv: Ut are located from which cv may be calculated.

CHAPTER 6CONCLUSION

All the test has met the aim and objectives that set up earlier as the following conclusion can be drawn based on the findings :

ParametersResultDesription

Type of soilWell Graded/Poorly GradedSilty SandSee table 4.3 and Figure 4.4 : The recommended standard for soil classification is the British Soil Classification System, and this is detailed in BS 5930 Site Investigation. Its essential structure is as follows:

The percentage of types of soil100%-60% = 40% (gravel)60%-6% = 54% (Sand)6% = (silt)

Table 4.4 : The recommended standard for soil classification is the British Soil Classification System, and this is detailed in BS 5930 Site Investigation. Its essential structure is as follows:

Plastic Limit17.72 %Figure 4.7 : Plasticity Chart based on British Standard

Liquid Limit33.30 %Figure 4.7 : Plasticity Chart based on British Standard

Plasticity Index15.58 %Figure 4.7 : Plasticity Chart based on British Standard

Cv1.85 m2/year

Based on engineering properties this state should conduct with undisturb sample but in lab the test was used remolded sample. The knowledge on consolidation of soil is important as it helps engineer to design effectively. With this, it easy to able to predict and design in way that settlement is minimized where are able to prevent damages towards buildings also with case study which is highways.

REFERENCES

1) http://civilengineeringlaboratory.blogspot.com/2012/02/liquid-limit-and-plastic-limit-tests.html2) https://www.dot.ny.gov/divisions/engineering/technical-services/technical-services-repository/GTM-7b.pdf3) https://www.mdt.mt.gov/other/materials/external/geotech_manual/chapter09.pdf4) http://www.vulcanhammer.net/geotechnical/EM-1110-2-1906.pdf5) Book : Soil Mechanics Fourth edition Roy Whitlow6) Book : Open Ended Lab Manual for Soil Mechanics Laboratory

30