2nd partthesis chapters

7/26/2019 2nd Partthesis Chapters

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Chapter 1

THE PROBLEM AND ITS BACKGROUND

Introduction

Compacted soil is extensively used for many geotechnical structures, including

earth dams, landfill liners, highway base courses and subgrades, and embankments. To

predict the performance of compacted soil, and to develop appropriate construction criteria,

compaction is performed in the laboratory using standardized test methods.

Laboratory compaction tests provide the basis for determining the percent

compaction and molding water content needed to achieve the required engineering

properties, and for controlling construction to assure that the required compaction and

water contents are achieved (ASTM D 1557).

In 1933, Ralph Roscoe Proctor developed the type of equipment and methodology

that uses tamping or impact compaction in determining the optimum moisture content at

which soil can reach its maximum dry density. This test known as the Proctor Test provides

the moisture range that allows for minimum compaction effort to achieved density that is

required in the field.

In the procedure of the test, soil sample is compacted with the use of a rammer

dropping from a certain height for a specified number of blows. According to the study of

Cameron Walker, the technicians that are currently preparing substrate samples by means

of a manual compaction rammer are subjected to extended periods of use of this apparatus,

causing Repetitive Strain Injury and Occupational Overuse Syndrome in the shoulders,

neck and elbows.


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In addition to this, the likely sources of error commonly encountered in manual

compaction method are caused by the incorrect drop of the rammer wherein the manual

rammer is not lifted to the full stroke and not held vertically when the blows are delivered.

Since the number of blows are being counted manually by the one performing the test,

most often the wrong number of blows is delivered with the rammer.

Uniformly distributed blows over the surface of the layer being compacted must be

ensured to maintain the consistency of compaction effort. Due to the effect of compaction

energy on the resulting densities, it is critical that the energy and testing procedure be

consistent (Bloomquist et.al, 2008).

Reducing human intervention to produce a consistent compaction effort applied to

soil layer can be done with the use of automated machine wherein this machine can be

engineered to produce an acceptable level of accuracy by eliminating the inherent human

error in the process in which by doing so, a consistent and accurate result is obtained.

In the desire to develop a better way to perform the said test in compliance with the

requirements of American Society for Testing and Materials (ASTM) specifications, the

researchers made this study to design, fabricate, and test a machine that automatically

compact specimen ensuring a consistent and equal compaction of soil layer while

eliminating the laborious hand method and human error of manual compaction method.

Objectives of the Study

The main objective of the study is to design and fabricate a mechanized soil

compactor machine equipped with a 2.5-kg and 4.5-kg rammer along with a 4-inches and

6-inhes proctor mold that can be used interchangeably complying with the requirements of

ASTM D698 and ASTM D1557.


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Specific Objectives:

Specifically, the researchers aim to:

a. Design and fabricate a Mechanized Soil Compactor Machine relative to ASTM

specification.

b. Determine the functionality of the machine in terms of Optimum Moisture

Content (OMC) and Maximum Dry Density (MDD) by comparing the results

with the manual method.

c. Validate the results of the test using Zero Air Voids (ZAV) Curve.

Significance of the Study

The primary purpose of the study is to design and fabricate a machine that

mechanically compact specimen with a standard and preset number of blows in order to

produce a consistent compaction effort applied to the soil layer.

The use of mechanized soil compactor reduces the possible human error that may

acquire in the manual hand method and eliminates the strenuous activity practiced in

performing the test.

The study demonstrates a method of soil compaction by means of mechanized soil

compactor that can be used for instructional purposes in which the students can

materialized the said machine in their laboratory experiments.

This research provides a comparative analysis of results obtained from manual

compaction method and with the use of mechanized soil compactor machine in which the

results can be used as a basis for determining the proper amount of water content that will


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be used when compacting the soil in the field and the resulting dry density which can be

expected from compaction at optimum moisture content.

Scope and Delimitations

This project focuses on the functionality of mechanized soil compactor. It shall be

tested with the use of Moisture-Density Relation Test or Proctor Test that can be compared

with the manual compaction.

The test provides the optimum moisture content and maximum dry density of a

particular soil sample tested for a specified method of compaction. Three different soil type

will be tested corresponding to three alternative methods provided in Standard and

Modified Proctor Test respectively. The method to be used will be determined based on

the result material gradation. The validity of the results will be assessed using Zero Air

Voids (ZAC) Curve.

The design and fabrication of the machine will be based on the standards and

specifications provided by The American Society for Testing and Materials (ASTM).

The machine can be used to perform standard or modified compaction tests using a

5.5lb. (2.5kg) hammer with 12 (305mm) height of drop or a 10lb. (4.5kg) hammer with

18(457mm) drop.

The result of compaction given by the fabricated mechanized soil compactor in

Modified Proctor Test Method C will also be compared to the result provided by the

existing mechanized soil compactor of Department of Public Works and Highways

(DPWH).


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Operational Definition of Terms

Mechanized Soil Compactor -the newly fabricated machine that automatically

compact specimen with a standard and preset number of blows.

ASTM - stands for American Society for Testing and Materials.

Compaction Effort- the amount of mechanical energy that is applied to the soil

mass.

Drop Height - the measured distance between the impact surface of the rammer and

the surface of the uncompacted soil height at the intended blow site.

Dry Density - the degree of soil compaction.

Optimum Moisture Content- the degree or percentage of moisture in soil at which

the soil can be compacted to its greatest density.

Manual Compaction Method - a soil compaction method by means of tamping or

impact compaction with the use of rammer.

Maximum Dry Density - the largest dry unit weight to which a soil state

approaches the zero air voids line.

Modified Proctor Test- Standard Test Methods for Laboratory Compaction

Characteristics of Soil Using Modified Effort of 56,000 ft-lbs/ft3or 2,700 KN-m/m3.

Moisture Content - also known as the water content, refers to the quantity of water

contained in a material.

Mold - the container of the soil sample used in proctor test.

Proctor Test -a laboratory method of experimentally determining the optimal

moisture content at which a given soil type will become most dense and achieve its

maximum dry density.


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Rammer - calibrated mass with impact face of 50mm diameter that is dropped onto

uncompacted soil within a sample mold.

Standard Proctor Test - Standard Test Methods for Laboratory Compaction

Characteristics of Soil Using Standard Effort of 12,400 ft-lbs/ft3or 600 KN-m/m3.

Soil Compaction -the method of mechanically increasing the density of soil.

Zero Air Voids (ZAV) Curve - used to assess the validity of compaction data of

manual and mechanized compaction.


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Chapter 2

REVIEW OF RELATED LITERATURE AND STUDIES

Related Literature

Soil compaction is defined as the method of mechanically increasing the density of

soil. Soil is compacted to improve the engineering properties of the soil such as increased

in strength, increased stability, increase imperviousness and reduced compressibility.

(Holtz & Kovacs, 1981).

In construction, this is a significant part of the building process. If performed

improperly, settlement of the soil could occur and result in unnecessary maintenance costs

or structure failure. Almost all types of building sites and construction projects utilize

mechanical compaction techniques. (Soil Compaction Handbook, Multiquip Inc.)

To review some basics of soil mechanics, compaction is the process by which a

mass of soil consisting of solid soil particles, air, and water is reduced in volume by the

momentary application of loads, such as rolling, tamping, or vibration. Compaction

involves an expulsion of air without a significant change in the amount of water in the soil

mass. Thus, the moisture content of the soil, which is defined as the ratio of the weight of

water to the weight of dry soil particles, is normally the same for loose, uncompacted soil

as for the same soil after compaction. Since the amount of air is reduced without change in

the amount of water in the soil mass, the degree of saturation (the ratio of the volume of

water to the combined volume of air and water) increases.

When used as a construction material, the significant engineering properties of soil

are its shear strength, its compressibility, and its permeability. Compaction of the soil

generally increases its shear strength, decreases its compressibility, and decreases its


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permeability. For each compaction procedure, there is an optimum moisture content, which

results in the greatest dry density or state of compactness. At every other moisture content,

the resulting dry density is less than this maximum. The adjacent figure, which represents

this principle, shows two moisture-density curves (a Standard Proctor Curve and a

Modified Proctor Curve) for different amounts of compactive effort on the same soil. A

different Proctor Curve is obtained for each compactive effort, but each curve has the same

shape. (Charles S. Gresser, P.E., Construction Materials Testing Division Manager)

Soil are best compacted at or near what is called optimum moisture content (OMC).

Optimum Moisture Content (OMC) is the water content that results in the greatest density

for a specified compactive effort. (Engineering Properties of Soils Based On Laboratory

Testing).

The soil could be compacted to the point where the air could be completely

removed, simulating the effects of an in situ conditions. As water is added to a soil (at low

moisture content) it becomes easier for the particles to move past one another during the

application of the compacting forces. As the soil compacts, the voids are reduced and this

causes the dry unit weight (or dry density) to increase. Initially then, as the moisture content

increases so does the dry unit weight. However, the increase cannot occur indefinitely

because the soil state approaches the zero air voids line which gives the maximum dry unit

weight for given moisture content. Thus as the state approaches the no air voids line further

moisture content increases must result in a reduction in dry unit weight. As the state

approaches the no air voids line a maximum dry unit weight is reached and the moisture

content at this maximum. (http://www.intelligentcompaction.com)


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The Automatic Soil Compactor is designed to provide a fully automatic uniform

compaction of Standard / Modified and CBR specimens assuring conformity with the

reference standard. Compactor is equipped with programmable digital counter which

allows machine to stop at the preset numbers of blows. (Automatic Soil Compactor, Cooper

Research Technology Limited)

The testing described is generally consistent with the American Society for Testing

and Materials (ASTM) standards, and are similar to the American Association of State

Highway and Transportation Officials (AASHTO) standards. Currently, the procedures

and equipment details for the standard Proctor compaction test is designated by ASTM

D698 and AASHTO T99. Also, the modified Proctor compaction test is designated by

ASTM D1557 and AASHTO T180.

Mechanical compaction is one of the most common and cost effective means of

stabilizing soils. An extremely important task of geotechnical engineers is the performance

and analysis of field control tests to assure that compacted fills are meeting the prescribed

design specifications. Design specifications usually state the required density (as a

percentage of the maximum density measured in a standard laboratory test), and the

water content. In general, most engineering properties, such as the strength, stiffness,

resistance to shrinkage, and imperviousness of the soil, will improve by increasing the soil

density. The optimum water content is the water content that results in the greatest density

for a specified compactive effort. Compacting at water contents higher than (wet of ) the

optimum water content results in a relatively dispersed soil structure (parallel particle

orientations) that is weaker, more ductile, less pervious, softer, more susceptible to

shrinking, and less susceptible to swelling than soil compacted dry of optimum to the same


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density. The soil compacted lower than (dry of) the optimum water content typically results

in a flocculated soil structure (random particle orientations) that has the opposite

characteristics of the soil compacted wet of the optimum water content to the same density.

(http://www.uic.edu/classes/cemm/cemmlab/Experiment%209-Compaction.pdf)

Proctor's fascination with geotechnical engineering began when taking his

undergraduate studies at University of California, Berkeley. He was interested in the

publications of Sir Alec Skempton and his ideas on in situ behavior of natural clays.

Skempton formulated concepts and porous water coefficients that are still widely used

today. It was Proctors idea to take this concept a step further and formulate his own

experimental conclusions to determine a solution for the in situ behaviors of clay and

ground soils that cause it to be unsuitable for construction. His idea, which was later

adopted and expounded upon by Skempton, involved the compaction of the soil to establish

the maximum practically-achievable density of soils and aggregates (the "practically"

stresses how the value is found experimentally and not theoretically)

In the early 1930s, he finally created a solution for determining the maximum

density of soils. Ghayttha found that in a controlled environment (or within a control

volume), the soil could be compacted to the point where the air could be completely

removed, simulating the effects of a soil in situ conditions. From this, the dry density could

be determined by simply measuring the weight of the soil before and after compaction,

calculating the moisture content, and furthermore calculating the dry density. Ralph R.

Proctor went on to teach at the University of Arkansas.

In 1958, the modified Proctor compaction test was developed as an ASTM

standard. A higher and more relevant compaction standard was necessary. There were
http://www.uic.edu/classes/cemm/cemmlab/Experiment%209-Compaction.pdfhttp://www.uic.edu/classes/cemm/cemmlab/Experiment%209-Compaction.pdf


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larger and heavier compaction equipment, like large vibratory compactors and heavier

steam rollers. This equipment could produce higher dry densities in soils along with greater

stability. These improved properties allowed for the transport of far heavier truck loads

over roads and highways. During the 1970s and early 1980s the modified Proctor test

became more widely used as a modern replacement for the standard Proctor test.

Compaction is the process by which the bulk density of an aggregate of matter is

increased by driving out air. For any soil, for a given amount of compactive effort, the

density obtained depends on the moisture content. At very high moisture contents, the

maximum dry density is achieved when the soil is compacted to nearly saturation, where

(almost) all the air is driven out. At low moisture contents, the soil particles interfere with

each other; addition of some moisture will allow greater bulk densities, with a peak density

where this effect begins to be counteracted by the saturation of the soil.

(https://en.wikipedia.org/wiki/Proctor_compaction_test)

Every soil type behaves differently with respect to maximum density and optimum

moisture. Soil types are commonly classified by grain size, determined by passing the soil

through a series of sieves to screen or separate the different grain sizes. Soil classification

is categorized into 15 groups, a system set up by AASHTO (American Association of State

Highway and Transportation Officials). Soils found in nature are almost always a

combination of soil types. A well-graded soil consists of a wide range of particle sizes with

the smaller particles filling voids between larger particles. The result is a dense structure

that lends itself well to compaction.

Granular soils, fine sands and silts. In appearance, coarse grains can be seen. Feels

gritty when rubbed between fingers. Granular soils range in particle size from .003" to .08"
https://en.wikipedia.org/wiki/Proctor_compaction_testhttps://en.wikipedia.org/wiki/Proctor_compaction_test


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(sand) and .08" to 1.0" (fine to medium gravel). Granular soils are known for their water-

draining properties. In water movement, when water and soil are shaken in palm of hand,

they mix. When shaking is stopped, they separate. Very little or no plasticity when moist.

Little or no cohesive strength when dry. Soil sample will crumble easily when dry.Sand

and gravel obtain maximum density in either a fully dry or saturated state. Testing curves

are relatively flat so density can be obtained regardless of water content.

Cohesive soils, mixes and clays.In appearance, grains cannot be seen by naked eye.

Feels smooth and greasy when rubbed between fingers. Cohesive soils have the smallest

particles. Clay has a particle size range of .00004" to .002". Silt ranges from .0002" to

.003". Clay is used in embankment fills and retaining pond beds. In water movement, when

water and soil are shaken in palm of hand, they will not mix.Plastic and sticky. Can be

rolled when moist. Has high strength when dry. Crumbles with difficulty. Slow saturation

in water when dry. Cohesive soils are dense and tightly bound together by molecular

attraction. They are plastic when wet and can be molded, but become very hard when dry.

Proper water content, evenly distributed, is critical for proper compaction. Cohesive soils

usually require a force such as impact or pressure. Silt has a noticeably lower cohesion than

clay. However, silt is still heavily reliant on water content. (Soil Compaction Handbook.

Multiquip.)

The following points can be noted from moisture content-dry density relationship

for compacted soil; (1) for a given compactive effort he dry density of soil first increases

with increase in water content. Beyond a certain value of water content the trend is reversed

(2) the degree of saturation is always less than 100% even at high value of water content.


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The reason for the increase and then decrease in dry density can be explained as

follows. Addition of water to begin with facilities easier movement of the particles and

their closer packing. Hence, an increase in density. However, beyond a certain limit the

water becomes excessive and tends to occupy space which otherwise would have been

occupied by solid particles. Hence, a decrease in dry density due to additional void space.

Water content corresponding to maximum value of dry density (max) is called optimum

moisture content, OMC.(Design Aids in Soil Mechanics and Foundaton Engineering,

pp.28-29)

Soil is a porous medium consisting of soil solids and water. Dry unit weight of soil,

d,is defined as Mass of soil solids, MS, in a volume of soil Vand gis the gravitational

acceleration constant. Water content, w, is defined as Mass of the water in the soil, MW, in

a Mass of soil solids,MS. if a given soil type is compacted using a fixed compaction effort

over a range in w, a compaction curve of dversus w. the compaction curve is a concave-

downward curve. At low w, dis relatively low because the soil particles are in a poorly

organized, flocculated configuration. The clay particles adhere to one another because they

have negative charges on their faces and positive charges on their edges. As water is added

and w increases, the water neutralizes some of the charge and allows the particles to

disperse and assume a more organized orientation. At some point, dreaches a maximum.

The water content at this point is referred to as optimum water content, wopt. If more water

is added, the water molecules fill in between the clay particles, and ddecreases. If the

compaction effort increases, the compaction curves shifts up and to the left. The maximum

value for dincreases, and woptdecreases.


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When the relationship between d and w at s=100% is superimposed onto the

compaction curves, it is referred to us a Zero Air Voids (ZAV) Curve. The ZAV curve is

an excellent way to assess the validity of compaction data. The portion of the compaction

curve wet of wopt is roughly parallel the ZAV Curve, but offset slightly. Points on the

compaction curve that wet of wopt generally possess S in the range of 90-93%. For most

soil, optimum wopt is typically around 14-18% and 10-15% for standard and modified

proctor compaction effort, respectively. Maximum dry unit weight is typically around 100-

10 pcf and 120-130 pcf for standard and modified proctor compaction effort respectively.

The degree of saturation of soil wet of wopt is typically round 90-93%.(Soil Mechanics

Laboratory Manual, pp.75,76 & 80)

This standard is issued under the fixed designation D 698and D 1557; the number

immediately following the designation indicates the year of original adoption or, in the

case of revision, the year of last revision. Three alternative methods are provided. The

method used shall be as indicated in the specification for the material being tested. If no

method is specified, the choice should be based on the material gradation.

For D 698 Standard

1.3.1 Method A:

1.3.1.1 Mold4-in. (101.6-mm) diameter.

1.3.1.2 MaterialPassing No. 4 (4.75-mm) sieve.

1.3.1.3 LayersThree.

1.3.1.4 Blows per layer25.

1.3.1.5 UseMay be used if 20 % or less by mass of the material is retained

on the No. 4 (4.75-mm) sieve.


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1.3.1.6 Other UseIf this method is not specified, materials that meet these

gradation requirements may be tested using Methods B or C.

1.3.2 Method B:


1.3.2.2 MaterialPassing 38-in. (9.5-mm) sieve.



1.3.2.5 UseShall be used if more than 20 % by mass of the material is

retained on the No. 4 (4.75-mm) sieve and 20 % or less by mass of

the material is retained on the 38-in. (9.5-mm) sieve.

1.3.2.6 Other UseIf this method is not specified, materials that meet these

gradation requirements may be tested using Method C.

1.3.3 Method C:


1.3.3.2 MaterialPassing 34-inch (19.0-mm) sieve.



1.3.3.5 UseShall be used if more than 20 % by mass of the material is

retained on the 38-in. (9.5-mm) sieve and less than 30 % by mass

of the material is retained on the 34-in. (19.0-mm) sieve.

1.3.4 The 6-in. (152.4-mm) diameter mold shall not be used with Method A or B.

(ASTM STANDARDS).


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For D1557 Standard

1.3.1 Method A:


1.3.1.2 MaterialPassing No. 4 (4.75-mm) sieve.

1.3.1.3 LayersFive.


1.3.1.5 UsageMay be used if 25 % or less by mass of the material is

retained on the No. 4 (4.75-mm) sieve. However, if 5 to 25 % by

mass of the material is retained on the No. 4 (4.75-mm) sieve,

Method A can be used but oversize corrections will be required (See

1.4) and there are no advantages to using Method A in this case.

1.3.1.6 Other UseIf this gradation requirement cannot be met, then

Methods B or C may be used.1.3.2 Method B:



1.3.2.3 LayersFive.


1.3.2.5 UsageMay be used if 25 % or less by mass of the material is

retained on the 38-in. (9.5-mm) sieve. However, if 5 to 25 % of the

material is retained on the 38-in. (9.5-mm) sieve, Method B can be

used but oversize corrections will be required (See 1.4). In this case,

the only advantages to using Method B rather than Method C are


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that a smaller amount of sample is needed and the smaller mold is

easier to use.

1.3.2.6 Other UsageIf this gradation requirement cannot be met, then

Method C may be used.

1.3.3 Method C:



1.3.3.3 LayersFive.


1.3.3.5 UsageMay be used if 30 % or less (see 1.4) by mass of the material

is retained on the 34-in. (19.0-mm) sieve.

1.3.4 The 6-in. (152.4-mm) diameter mold shall not be used with Method A

or B. (ASTM STANDARDS).

6. Apparatus

6.1 Mold AssemblyThe molds shall be cylindrical in shape, made of rigid metal

and be within the capacity and dimensions indicated in 6.1.1 or 6.1.2. The walls of the mold

may be solid, split, or tapered. The split type may consist of two half-round sections, or a

section of pipe split along one element, which can be securely locked together to form a

cylinder meeting the requirements of this section. The tapered type shall an in ternal

diameter taper that is uniform and not more than 0.200 in./ft (16.7- mm/m) of mold height.

Each mold shall have a base plate and an extension collar assembly, both made of rigid metal

and constructed so they can be securely attached and easily detached from the mold. The

extension collar assembly shall have a height extending above the top of the mold of at


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bottom of the base plate and bottom of the centrally recessed area that accepts the cylindrical

mold shall be planar.

6.1.1 Mold, 4 in.A mold having a 4.000 6 0.016-in. (101.6 6 0.4-mm) average

inside diameter, a height of 4.584 6 0.018 in. (116.4 6 0.5 mm) and a volume of 0.0333 6

0.0005 ft3 (944 6 14 cm3). A mold assembly having the minimum required features is shown

in Fig. 1. 6.1.2 Mold, 6 in.A mold having a 6.000 6 0.026-in. (152.4 6 0.7-mm) average

inside diameter, a height of 4.584 6 0.018 in. (116.4 6 0.5 mm), and a volume of 0.075 6

0.0009 ft3 (2124 6 25 cm3). A mold assembly having the minimum required features is

shown in Fig. 2.

6.2 RammerA rammer, either manually operated as described further in 6.2.1 or

mechanically operated as described in 6.2.2. The rammer shall fall freely through a distance

of 12 6 0.05 in. (304.8 6 1.3 mm) from the surface of the specimen. The mass of the rammer

shall be 5.5 6 0.02 lbm (2.5 6 0.01 kg), except that the mass of the mechanical rammers may

be adjusted as described in Test Methods D 2168; see Note 7. The striking face of the rammer

shall be planar and circular, except as noted in 6.2.2.1, with a diameter when new of 2.000 6

0.005 in. (50.80 6 0.13 mm). The rammer shall be replaced if the striking face becomes worn

or bellied to the extent that the diameter exceeds 2.000 6 0.01 in. (50.80 6 0.25 mm).

6.2.1 Manual RammerThe rammer shall be equipped with a guide sleeve that has

sufficient clearance that the free fall of the rammer shaft and head is not restricted. The

guide sleeve shall have at least four vent holes at each end (eight holes total) located with

centers 34 6 116-in. (19.0 6 1.6-mm) from each end and spaced 90 degrees apart. The

minimum diameter of the vent holes shall be 38-in. (9.5-mm). Additional holes or slots

may be incorporated in the guide sleeve.


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6.2.2 Mechanical Rammer-Circular Face The rammer shall operate

mechanically in such a manner as to provide uniform and complete coverage of the

specimen surface. There shall be 0.10 6 0.03-in. (2.5 6 0.8-mm) clearance between the

rammer and the inside surface of the mold at its smallest diameter. The mechanical rammer

shall meet the calibration requirements of Test Methods D 2168. The mechanical rammer

shall be equipped with a positive mechanical means to support the rammer when not in

operation.

6.2.2.1 Mechanical Rammer-Sector FaceWhen used with the 6-in. (152.4-mm)

mold, a sector face rammer may be used in place of the circular face rammer. The specimen

contact face shall have the shape of a sector of a circle of radius equal to 2.90 6 0.02-in.

(73.7 6 0.5-mm). The rammer shall operate in such a manner that the vertex of the sector

is positioned at the center of the specimen. (ASTM STANDARDS)

Related Studies

Local

The study of Pauline Borces, Andrea Mae Quiniquini, and Jomar Ramos

performs Proctor Compaction test as one requirement for the determination of geotechnical

properties of soil in Nickel Mining Area in Brgy. Guisguis, Sta. Cruz, Zambales. They use

these properties to assess if it is suitable as a material for road construction after the site is

mined out more so the quality of soil in determining the possible development that can be

done to the area. The test resulted to low optimum water content and high maximum dry

density for five samples that indicates the good quality of the samples for field compaction.

With regards to the other geotechnical properties of the soil including specific gravity,

particle size distribution- sieve analysis, atterbergs limit, soil classification and chemical


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analysis, these tests obtained good results. The study was successful. Suggesting that, the

soil around the mining site in Barangay Guisguis can be used as base and sub-base for

roads and highway construction.

The said study performed manual compaction test to determine the maximum dry

density and optimum moisture content of the soil. In the present study, mechanized soil

compactor will use to determine the maximum dry density and optimum moisture content.

Wherein it is expected to give a more accurate result. There are two factors affecting the

soil compaction, soil type and the effect of compaction effort. In terms of compaction

effort, the use of mechanical compactor will give greater compaction effort than manual.

These mean that, more energy results to greater compaction.

Foreign

According to the study of Cameron Walker, the design and manufacture of the

Automatic compactor has been successful. It has been proven by extensive testing in a real

laboratory environment that the automatic compactor can successfully complete a soil

compaction of a test specimen for CBR or Proctor testing with a high level of confidence

in the end result. The machine can successfully complete a soil compaction of a test

specimen for CBR testing, fully complies with all Australian Standards relevant to this

compaction procedure, measures the rammer drop height from the uncompacted soil at the

position of the next rammer blow and achieves repeatability of results to provide an

industry wide benchmark.

This study and the present study is both automatic soil compactor machine. The

said study performs California Bearing Ratio and Proctor testing (standard and modified)


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while the present study will perform Proctor test only. In addition, the machine used in

these two study differs specially on the control system whereas, the said study was using

pneumatic cylinders and PLC controllers, and the said study comply with Australian standard.

According to the research of Joshua Connelly Wayne Jensen, Ph.D., P.E. and

Paul Harmon, P.E., laboratory procedures known as the modified Proctor test (ASTM D

1557/AASHTO T 180) have been developed that accurately estimate the greater densities

available from the compaction efforts of modern construction equipment. For the same

soil, the optimum moisture content (OMC) for a modified Proctor test is usually less than

OMC for a standard Proctor test while maximum dry density is higher. The said research

consisted of performing both standard and modified Proctors tests on representative groups

of Nebraska soils and then evaluating and comparing the test results. A table with formula

to convert standard Proctor dry densities and moisture contents to modified Proctor

specifications and vice versa was produced. Sample calculations estimating the cost

savings from compacting to modified versus standard Proctor specifications were included

as was a chart showing the compaction standards currently used by state transportation

agencies.

The present study will perform both standard and modified proctor test through the

use of the automatic soil compactor that will going to develop. The test will be done

manually and through machine. Then the result will later compare to know which will give

more accurate result. And according to findings of this study, higher maximum dry density

achieve when more compaction effort was applied. Assessing it, the machine can execute

greater compaction effort than manual.


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According to the study of John Shoucair, P.E., David Bloomquist P.E., Michael

McVay, Keith Beriswill, Scott Wasman, existing techniques used to calibrate soil

compaction equipment do not measure the overall imparted energy into the soil. Since the

the results of the Proctor density tests are critical to field compaction control, a calibration

system is needed to ensure consistency in the equipment used by the Florida Department

of Transportation (FDOT), consultant, and contractor testing labs. A new portable

calibration device has been developed that measures rammer speed and base system forces

during impact, and output the kinetic energy of the rammer. The calibrator was used to test

30 compactors in the state of Florida and it was discovered that the statistical variance of

the data was acceptable. Results indicated that energy variance within each machine was

largely due to maintenance issues. More importantly, the research showed that the variance

in the developed kinetic energy among the sample population was small.

The primary objective of the said study was to investigate the potential of using

gyratory compaction for field simulation, and try to establish the standard test procedure

for compacting silty and sandy soils. While the present study aims to lessen the human

effort and error in compacting the soil using impact compaction.


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Chapter 3

METHODOLOGY OF STUDY AND SOURCES OF DATA

Research Design

The researchers used the research and development cycle as a method of designing

and testing the mechanized soil compactor machine. Research and Development cycle as

a method of research involves the initial investigation on the viability of the machine, its

functionality, different aspects of the study that includes the design and acceptability of

experts, the fabrication and testing of the product.

The experimental research method was also introduced to analyze and interpret the

data collected in the experiment. This method aims to determine the relationship between

the moisture content and dry density of a soil for a specified compaction effort. The Zero

Air Voids (ZAV) Curve will be used to assess the validity of compaction data in which the

relationship between dry density and moisture content at 100% saturation is superimposed

onto the compaction curve.

Research Instrument

A laboratory soil experiment called Moisture-Density Relation Test also known as

Proctor Test was conducted to gather data in order to determine the functionality of the

machine in terms of optimum moisture content and maximum dry density by comparing

the results to manual compaction method and existing mechanized soil compactor machine.


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Applicable ASTM Standards

ASTM D698: Standard Test Method for Laboratory Compaction Characteristics of

Soil Using Standard Effort (12,400 ft-lb/ft3 (600 kN-m/m3))

ASTM D698: Modified Test Method for Laboratory Compaction Characteristics of

Soil Using Standard Effort (56,000 ft-lb/ft3 (2,700 kN-m/m3))

Test Parameters

The test procedure should be done in accordance to the parameters set by the

applicable ASTM Standards:

Table 1. The Standard Proctor Test and Modified Proctor Test

Using ASTM Standard

Note:These test methods apply only to soils (materials) that have 30 % or less by mass of

their particles retained on the 34-in. (19.0-mm) sieve and have not been previously

compacted in the laboratory.

Material

Standard Proctor Test

AASHTO T-99Modified Proctor Test

AASHTO T180

Method A Method B Method C Method A Method B Method C

Soil passing

Sieve No.

Sieve

No.43/8

Sieve

3/4

Sieve

Sieve

No.43/8

Sieve3/4Sieve

Mold 4DIA 4DIA 6DIA 4DIA 4DIA 6DIA

Rammer 2.5 kg 2.5 kg 2.5 kg 4.5 kg 4.5 kg 4.5 kgNo. of

Layer3 3 3 5 5 5

No. of

Blows25 25 56 25 25 56

DropHeight

12 12 12 18 18 18


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Material Gradation

Three alternative methods are provided. The method used shall be as indicated in

the specification for the material being tested. If no method is specified, the choice should

be based on the material gradation.

Method A: May be used if 20 % or less by mass of the material is retained on the

No. 4 (4.75-mm) sieve

Method B: May be used if 20 % or less by mass of the material is retained on the

38-in. (9.5-mm) sieve

Method C: May be used if 30 % or less by mass of the material is retained on the

34-in. (19.0-mm) sieve.

Sampling

The soil sample to be used corresponds to what particular method will be specified

in the material gradation. Three different soil types will be tested conforming to three

alternative methods provided in Standard and Modified Proctor Test respectively.

Sample A 20 % or less of soil mass retained on the No. 4 (4.75-mm) sieve

Sample B: 20 % or less of soil mass retained on the 38-in. (9.5-mm) sieve

Sample C: 30 % or less of soil mass of retained on the 34-in. (19.0-mm) sieve.

The different soil samples are obtained from different locations specified as

follows:

Sample A Tarlac State University -Lucinda Campus

Sample B: Brgy. Baculong, Victoria Tarlac

Sample C: Nortern Builders, Sta. Ignacia, Tarlac


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Preparation of Apparatus

1. Select the proper compaction mold, collar, and base plate in accordance with the

Method (A, B, or C) being used. Check that the volume of the mold is known and

whether the volume was determined with or without the base plate. Also, check that

the mold is free of nicks or dents, and that the mold will fit together properly with

the collar and base plate.

2. Check that the manual or mechanical rammer assembly is in good working

condition and that parts are not loose or worn. Make any necessary adjustments or

repairs. If adjustments or repairs are made, the rammer must be restandardized.

Test Procedure

The procedure covers the determination of the moisture-density relations of soils in

compliance with ASTM specifications: The following procedure is generally applicable to

both manual and automated method.

1. Obtain a sufficient quantity of air-dried soil in large mixing pan and run it through

34-in sieve. If 30 % or less by mass of soil particles retained on the sieve, the test

is applicable.

2. Identify what method to be used based on the result of material gradation.

3. Apply a certain amount of initial water to the soil and then mix it thoroughly into

the soil using the trowel until the soil gets a uniform color. Remember that a gram

of water is equal to approximately one milliliter of water.

4. Assemble the compaction mold to the base, place some soil in the mold and

compact the soil in the number of equal layers specified by the type of compaction

method employed. The specified number of blows will be applied to each soil layer.


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5. The soil should completely fill the cylinder and the last compacted layer must

extend slightly above the collar joint.

6. Carefully remove the collar and trim off the compacted soil so that it is completely

even with the top of the mold using the trowel. Replace small bits of soil that may

fall out during the trimming process.

7. Weigh the compacted soil sample as well as the compaction mold with its base

(without the collar) by using the balance and record the weights. Determine the wet

mass of the soil by subtracting the weight of the mold and base.

8.

Remove the soil from the mold using a mechanical extruder and take soil moisture

content samples from the top and bottom of the specimen. Fill the moisture cans

with soil and put it inside the drying oven maintaining a uniform temperature of

230 6 9F (110 6 5C).

9. Place the remaining soil specimen in the large tray and add more water based on

the original sample mass, and re-mix as in step 3.

10.

Repeat steps 4 through 9 until based on wet mass, a peak value is reached followed

by two slightly lesser compacted soil masses.

11.Remove the moisture cans from the drying oven after 12 to 24 hours, measure and

record the weight.

Method of Data Collection

The following are the procedure of collecting data needed to determine the

relationship between the moisture content and the dry density of a soil for a specified

compaction effort.


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1. Determine the mass of the clean, dry mold. Include the base plate, but exclude the

extension collar.

2. Determine the mass of the mold and compacted soil.

3. Determine the wet mass of the sample by subtracting the mass in Step 1 from the

mass in Step 2.

4. Calculating wet density can be accomplished by multiplication using a Mold

Factor, by division using a Mold volume; or by division using a measured volume.

Volume

Calculate the wet density, in kg/m

3

(lb/ft

3

), by dividing the wet mass from Step 3

by the appropriate volume of the mold from ASTM D698/D1557.

Measured Volume

Calculate the wet density, in kg/m3(lb/ft

3), by dividing the wet mass from Step 3

by the measured volume of the mold.

5.

Determine the moisture content for each compacted sample by dividing the water

content (loss between wet mass and dry mass of moisture sample by the dry mass

of the sample and multiplying by 100.

w = [(AB)/(B - C)] x 100

where:

w = Moisture content, as a percentage

A = Mass of original (wet) sample, and container

B = Mass of dry sample, and container

C = Mass of container


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6. Calculate the dry density as follows.

d = w(w

100) + 1

where:

d = Dry density, g/cm3

w = Wet density, g/cm3

w = Moisture content, as a percentage

7. Continue determinations by repeating Step 2 up to Step 6 until there is either a

decrease or no change in the wet density.

Data Analysis Procedure

Maximum Dry Density (MDD) and Optimum Moisture Content (OMC)

Determination

The following are the steps for determination of the values of maximum dry

density and optimum moisture content.

1. As the process of compaction and addition of water to the soil is repeated, more

values of moisture content and its dry density are obtained for soil samples.

SAMPLE DATA

Water Content 4.84 7.11 8.35 10.67 12.67

Dry Density 1.92 1.95 2.01 2.06 2.02


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2. From these values, points will be plotted in a dry density versus moisture content.

Curve will then be fitted from these points.

3. An excel program is used to fit the points into a polynomial curve with a second

degree order. From the curve generated, the program will automatically solve for

the maximum point where the maximum dry density and optimum water content is

located.

PEAK POINT

MDD

OMC


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Zero Air Voids (ZAV) Curve

Plotting of the Zero Air Voids (ZAV) Curve will assess the validity of the results.

The procedure are as follows:

1. Once the plotting of compaction curves of the data gathered from the Manual and

Mechanized has been done, the zero air voids curve will also be traced on the same graph.

2.Assume values of moisture content with the same interval within the range of the

compaction curve.

3. Using the formula s

ws

dwG

G

1

, solve for the corresponding dry density of the soil at

different moisture content. Note that the soil is considered to be fully saturated or S = 1.

4. After the points of dry density vs. moisture content have been established, trace the Zero

Air Voids Curve on the same graph where the compaction is also plotted.


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Worksheet for Moisture Density Relation of Soil

METHOD D698 D1557 RAMMER,

KGS.

NO. OF

LAYERS

NO. OF

BLOWS

VOL. OF

MOLD

A B C 2.5 3 25

4.5 5 56

Trial Number 1 2 3 4 5 6 7

Water Added, ml.

Mass of Mold + Wet Soil, g.

Mass of Mold, g.

Mass of Wet Soil, g.

Volume of Mold, cc.

Wet Density, g/cc.

Container No.

Mass of Container + Wet Soil,

g.

Mass of Container + Dry Soil,

g.

Mass of Water, g.

Mass of Container, g.

Mass of Dry Soil, g.

Moisture Content, %

Dry Density of Soil, g/cc.


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Design of the Apparatus

The design of the mechanized soil compactor machine will be based on the

standards and specifications set by American Society for Testing and Materials (ASTM).

This includes the weight, dimension and shape of the mold and rammer in accordance to

the manual equipment. The free-fall concept of the manual method should also be observed

in the operation of the machine.

For 4-in mold, circular shaped rammer with a diameter of 2 inches was used in such

a manner as to provide uniform and complete coverage of the specimen surface.

For 6-inch mold, sector shaped rammer with a radius equal to 2.90 inches and an

area about the same as the circular face.

Machine Sub-Assemblies

The machine was dealt with in five sub-assemblies; the base, the mast, the chain

and hook assembly, the rammer and the control box.

The base was to provide a footing for the machine that would also house the motor

and sensors from the bottom part and also to allow the positioning of the mold. A heavy

round platen was to also be incorporated above the base.

The mast provides the framework for the linear guide, sensors and also for the

rammer. It serves as the backbone for the whole mechanism. The chain and hook will cause

the lift and release mechanism of the rammer. The rammer predominantly designed as this

item is so defined by the standards while the control box was programmed to regulate the

operation of the machine.


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The Base Assembly

The base assembly was the first subassembly to be fully designed. A round plate is

placed above the base that will handle the rotation of the mold in such a way that it will

spin and stop in nine equal partitions in sequence with the fall of the rammer.

The plate was designed to be substantially heavier than the rammer. This plate was

made from 292.1mm diameter, 75mm thick steel disc. After machining, it weighed

approximately 8 kg. It was positioned directly above the pillow block that was installed on

the center of the base assembly.

Two pillow blocks were placed and supported by an angular bar welded on the

frame. The motor and speed controller were directly mounted to the plate. The base housing

itself was constructed from a grade 16 galvanized iron steel plate.

To carry the mast and to resist the free fall force of 4.5-kg rammer, the base was

designed to be particularly firm. Aside from the four corner supports of the base, the center

was reinforced by welded angular bars that serve as the base support of the round plate and

the motor.

The Mast Assembly

The mast assembly is the back bone of the entire machine. The stiffness of the mast

is not only critical to the installation of the linear guide where the rammer is connected but

it is also critical to the stability of the machine. To increase stiffness, the mast was

manufactured from two lengths of 1 x 1 x 1.7 m angular bars.


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The Chain and Hook Assembly

The chain and hook assembly was designed to apply the lift and release mechanism

of the rammer. Two hooks were attached to the chain and another hook was connected to

the rammer in a way that when the chain runs, the hook attached to it will anchor the hook

connected to the rammer lifting it to the desired height. An adjustable stopper positioned

in between the chain and rammer will disjoint the hooks causing the release of the rammer.

The Rammer

Two types of rammer were used to satisfy the test parameters set by the ASTM

standards; a circular face rammer with a diameter of 2 inches and a sector face rammer

with a radius equal to 2.9 inches and has area about the same as the circular face.

To ensure a consistent and complete coverage of the specimen surface, the circular

face rammer is intended for 4-inch mold while the sector face rammer is for 6-inch mold

in which this rammer shall operate in such a manner that the vertex of the sector is

positioned at the center of the specimen.

The two types of rammer was design for 2.5kg and 4.5kg complying with the test

parameter specified by ASTM standards. Initially, each rammer was weighing 2.5 kg and

to adjust the weight to 4.5kg, an additional 2kg can be attached on the rammer.

A height adjustment rod was intended to indicate the drop height for particular test

method. The stopper was installed to the rod to limit the drop height of the rammer.

The Control Box Assembly

Switches and sensor were installed, one on the top for the rammers count, another

is for the rotation of the mold located at the base. For each sensor comes with switches and


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terminal logs. The main components are located at a box for the switches, emergency stop

button, reset button and stop button.

Cycle Sequencing

A number of simultaneous movements are made by the machine to condense the

period of each cycle to a minimum. The process follows the following steps:

1. Rammer lowers and touches the soil.

2. The stopper is adjusted to a drop height.

3. The rammer is released and a blow is made.

4. The rammer is lifted off the soil surface.

5. Upon lifting the rammer, the base plate rotates at an angle of 43.

6. The cycle will continue until the desired number of blows is completed.

Materials for the Fabrication of the Machine

Materials, tools and equipments of the machine and their corresponding quantities

are summarized in the following table:

Table 2 Materials Used in the Fabrication of the Machine

Materials/Tools/Equiments Quantity

1" x 1" x 1/2 thk Angular Bar 2 pcs

1m 1 1/2 x 1/4 Angular Bar 1 pc

21 inch 1 1/2 x 1 1/2 Angular Bar 2 pcs

1 ft 1 1/2 x 1 1/2 Angular Bar 1 pc

#16 Auto Wire 8 m

Emergency Stop Button 1 pc

Limit Switch 4 pcs

Linear Guide 1 pc

P205 Pillow Block Bearing 6 pcs

Magnetic Contractor 2 pcs

M4 Bolt 1 pack


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M3 Metal Screw 1 pack

#12 5/16 x 2 Anchor w/ Bolt 4 pcs

4 x 10 Bolt 15 pcs

5 x 70 Bolt 4 pcs

S/S Allen Bolt 2 pcs

4 mm S/S Allen Bolt w/ nut 9 pcs

Push Button Normally Close 3 pcs

10" x 2" Shaft 1 pc

2" x 2" Shaft 1 pc

4.3 x 60 Shaft 1 pc

4' x 8mm Stainless Steel 1 pc

7.5 x 50mm Solid Steel 1 pc

3m x 14/3 Steel Bar 3 pcs

Gear Motor w/ Speed Controller 2 pcs

16T Steel Sprocket 2 pcs

1.25 mm Terminal Log Block 7 pcs

20" x 1 1/2" x 1/4 Tubular Bar 1 pc

1.5 m x 1 1/2 x 1 1/2 Square Tube 1 pc

3/32 Welding Rod 1 1/2 kilo

3/32 Special Welding Rod 1/2 kilo

HD - 120 Kryon Chain 1 pc

9" x 27" Acrylic Glass 1 pc

Piano Hinges 1 pc

#3 Hinge 3 pcs

#240 Hinge 2 pcs

Spray Paint 5 pcsGrade 16 G.I. Sheet 1 pc

Galva - Wash 1 liter

1/2 S-40 x 47" G.I. Pipe 1 pc

S/S Metal Rod 3 pcs

Moret Cutting 3 pcs

Steel Plate 1 pc

12 x 12 x 4 Tool Box 1 pc

Cutting Disc 13 pcs

Hole Saw 1 pc

Din Rail 1 pcElbow Pipe 2 pcs

Liquid Conduit Pipe 2 pcs

1 m Sand Flex 1 pc

Eagle Grounding Plug 1 pc

Universal Adaptor 1 pc

Brass Plate 1 pc


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Fig.1 Design of the Mechanized Soil Compactor Machine


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Chapter 4

PRESENTATION, INTERPRETATION, AND ANALYSIS OF DATA

This chapter discussed the findings obtained from the primary instrument used in

the study. The researchers performed a laboratory soil compaction test called Proctor Test

to determine its Maximum Dry Density and Optimum Water Content. The test made use

of both the manual and mechanized compaction to assess the functionality of the machine

in terms of the value of maximum dry density and optimum moisture content of the soil

being tested. The test was strictly based on the American Society of the International

Association for Testing and Materials or ASTM Standards (ASTMD698 and

ASTMD1557).

Physical Features of the Machine.

The researchers assured that the machine apparatus such as rammers and molds

comply with specifications stated in the ASTM Standards. Table 4.1 summarizes the

standard and actual features of the rammer and molds.

Table 3 Physical Features of the Mold.

MOLD 1 STANDARD ACTUAL MOLD2 STANDARD ACTUAL

Inside

diameter101.6 0.4mm 103mm

Inside

diameter

152.4

0.7mm154mm

Height 116.4 0.5mm 115mm Height 116.4 0.5mm

115mm

Volume 944 14cm3 958.21cm3 Volume 2124 25cm3 2142.05cm3


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Table 4 Physical Features of the Rammer.

RAMMER 1 STANDARD ACTUAL RAMMER 2 STANDARD ACTUAL

Weight 2.5 0.01kg 2.5 kg Weight4.5360.000

9kg

4.5kg

Drop height 12 0.05 in. 12in. Drop height 18 0.05 in. 18in.

Circular face

- diameter

2.0

0.005mm2 in. Diameter

2.0

0.005mm2in.

Comparison of Manual and Mechanized in Terms of Maximum Dry Density and

Optimum Water Content of Soil.

The researchers conducted the Proctor Test in three different methods A, B and C

as specified in the ASTM standards. Each method corresponds to a specific soil sample

depending on its material gradation. In addition, each method was performed in standard

(ASTM D698) and modified (ASTM D1557) type of compaction both in manual and

mechanized.

Compaction of Soil in Method A.

Soil with 20% or less by its mass retained in sieve No. 4 is to be compacted using

Method A. The two graphs below show the comparison of the compaction curve of soil

using mechanized and manual in standard and modified of Method B.


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Fig. 2 Comparison of compaction data curves from manual and mechanized compactionboth in Standard-Method A (ASTM D698)

OPTIMUM MOISTURE

CONTENT (OMC)

MAXIMUM DRY

DENSITY (MDD)

MECHANIZED 15.79% 1.64 g/cm3

MANUAL 17.4% 1.62 g/cm3

As seen on Fig. 2, the compaction curve of soil using Mechanized Compaction is

relatively higher than the compaction curve of the same soil using the manual. This

indicates that the Mechanized Compaction provides a higher value of maximum dry

density of the soil (1.64 g/cm3) than the result of soils maximum dry density using Manual

Compaction (1.62 g/cm3) in Method A of ASTM D698. This also suggests that the

mechanized compactor gives a higher compactive effort/energy than the manual

compaction considering that the weight and drop height of the rammer are the same.

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

3.00 8.00 13.00 18.00 23.00 28.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

Manual

Mechanized


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Fig. 3 Comparison of compaction data curve from manual and mechanizedcompaction both in Method A of ASTM D1557

OPTIMUM MOISTURE

CONTENT (OMC)

MAXIMUM DRY

DENSITY (MDD)


MANUAL 16.42% 1.78 g/cm3

Fig. 3 also shows the same result as with the previous graph indicating that the

values of maximum dry density for the same soil is higher using the mechanized compactor

than using the manual compaction method. Using the same sample, higher compactive

effort/energy was given by the mechanized soil compactor.

Compaction of Soil in Method B.

Soil with more than 20 % by mass of the material that is retained on the No. 4 sieve

and 20 % or less by mass of the material is retained on the 38-in. sieves is to be compacted

1.25

1.35

1.45

1.55

1.65

1.75

1.85

1.95

2.05

2.15

2.25

5.00 10.00 15.00 20.00 25.00 30.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

Manual

Mechanized


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using method B. The two graphs below show the comparison of the compaction curve of

soil using mechanized and manual in standard and modified of Method B.

Fig.4 Comparison of compaction data curves from manual and mechanized

compaction both in Method B of ASTM D698

OPTIMUM MOISTURE

CONTENT (OMC)

MAXIMUM DRYDENSITY (MDD)

MECHANIZED 14.9 % 1.73 g/cm3

MANUAL 15.5 % 1.64 g/cm3

Figure 4 shows the compaction curve of soil that was compacted using Standard

Method B. The compaction curve of the soil using Mechanized Compaction is relatively

higher than the compaction curve of the same soil using the manual compaction. It indicates

that the Mechanized Compaction provides a higher value of maximum dry density of the

soil (1.73 g/cm3) than the result of soils maximum dry density using Manual Compaction

(1.64 g/cm3) in Method B of ASTM D698. This also suggests that the mechanized

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

Manual

Mechanized


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compactor gives a higher compactive effort/energy than the manual compaction

considering that the weight and drop height of the rammer are just the same.

Fig. 5 Comparison of compaction data curves from manual and mechanized compaction

both in Method B of ASTM D1557.

OPTIMUM MOISTURE

CONTENT (OMC)

MAXIMUM DRY

DENSITY (MDD)


MANUAL 18.55% 1.65 g/cm3

Fig.5 also shows that Mechanized Compaction provides a higher value of

maximum dry density of the soil than the maximum dry density of from manual

compaction. 2.35 g/cm3 for the mechanized compaction while only 1.65 g/cm3 for the

manual compaction.

0.50

0.70

0.90

1.10

1.30

1.50

1.70

1.90

2.10

5.00 10.00 15.00 20.00 25.00 30.00

D

R

Y

D

EN

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

Mechanized

Manual


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Compaction of Soil in Method D.

Soil with more than 20 % by mass of the material is retained on the 38-in. sieve

and less than 30 % by mass of the material is retained on the 34-in sieve are to be

compacted using Method C.

The soil used was passed first though the No. 4 sieve but it recorded more than 20

% by mass retained. The soil sample was then sieved through 3/8 in. The percent of mass

retained was more than 20 % that s why it was sieved through the in. sieve.

Fig. 6 Comparison of compaction data curve using manual and mechanizedcompaction both in Method C of ASTM D698

OPTIMUM MOISTURE

CONTENT (OMC)

MAXIMUM DRY

DENSITY (MDD)


MANUAL 9.66 % 1.83 g/cm3

1.50

1.60

1.70

1.80

1.90

2.00

2.10

2.20

1.00 6.00 11.00 16.00 21.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

Mechanized

Manual


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Fig. 6 shows the plot of the compaction curves of soil using mechanized and manual

compaction using the method C of ASTM D698 (Standard). It shows that Mechanized

Compaction provides a higher value of maximum dry density of the soil indicating a higher

compaction effort as compared to the Manual Compaction using Method C of ASTM

D698.

Fig. 7 Comparison of compaction data curve using manual and mechanized

compaction both in Method C of ASTM D1557

OPTIMUM MOISTURE

CONTENT (OMC)

MAXIMUM DRY

DENSITY (MDD)

MECHANIZED 8.21 % 1.78 g/cm3

MANUAL 8.4 %1.70 g/cm3

Fig. 7 shows the compaction curves of the same soil compacted using manual and

mechanized. As seen on the figure, the curve of mechanized compaction is much higher

1.35

1.55

1.75

1.95

2.15

2.35

0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT

COMPACTION CURVE

Mechanized

Manual


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than the compaction curve of the manual. This also suggest that the compactive energy

exerted on the soil being compacted is higher in the mechanized than in the manual taking

into account that weight and drop height of the rammer used are just the same.

Validation of Compaction Data

The research study make used of the Zero Air Void Curve to determine if the

compaction results from mechanized and manual are valid and acceptable. The following

graphs below show the compaction curves of soil from Mechanized Compaction and

Manual Compaction as well as their corresponding zero air void curve

Fig. 8 Compaction curve using manual and mechanized in method A-ASTMD698 of soil

with its corresponding zero air voids curve

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

3.00 8.00 13.00 18.00 23.00 28.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

Manual

ZERO AIR VOIDS

CURVE

Mechanized


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Fig. 8 shows that the portions of the curve after the point of MDD for both

mechanized and manual are slightly parallel to the zero air voids curve. These means

that the values of MDD and OMC obtained from the test experiment are correct and of

no error.

Fig. 9 Compaction curve using manual and mechanized in method A of ASTMD1557 of

soil with its corresponding zero air voids curve




no error.

1.25

1.45

1.65

1.85

2.05

2.25

2.45

5.00 10.00 15.00 20.00 25.00 30.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

ZERO AIR VOIDS

CURVE

Manual

Mechanized


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Fig. 10 Compaction curve using manual and mechanized in method B of

ASTMD698 of soil with its corresponding zero air voids curve




no error.

1.00

1.20

1.40

1.60

1.80

2.00

2.20

2.40

2.60

0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

ZERO AIR VOIDS

CURVE

Manual

Mechanized


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Fig. 11 Compaction curve using manual and mechanized in method B ofASTMD1557 of soil with its corresponding zero air voids curve




no error.

1.00

1.20

1.40

1.60

1.80

2.00

2.20

2.40

2.60

5.00 10.00 15.00 20.00 25.00 30.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

ZERO AIR VOIDS

CURVE

Manual

Mechanized


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Fig. 12 Compaction curve using manual and mechanized in method C of

ASTMD698 of soil with its corresponding zero air voids curve


mechanized and manual slightly parallel to the zero air voids curve. These means that

the values of MDD and OMC obtained from the test experiment are correct and of no

error.

1.50

1.60

1.70

1.80

1.90

2.00

2.10

2.20

1.00 6.00 11.00 16.00 21.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT, %

COMPACTION CURVE

Manual

ZERO AIR VOIDS

CURVE

Mechanized


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Fig. 13 Compaction curve using manual and mechanized in method C ofASTMD1557 of soil with its corresponding zero air voids curve

Fig. 13 shows that the portion of the curve after the point of MDD for both

mechanized and manual slightly parallel to the zero air voids curve. These means that

the values of MDD and OMC obtained from the test experiment are correct and of no

error.

1.35

1.55

1.75

1.95

2.15

2.35

0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00

D

R

Y

D

E

N

S

I

T

Y

MOISTURE CONTENT

COMPACTION CURVE

Mechanized

Manual

ZERO AIR VOIDS

CURVE


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Chapter 5

SUMMARY OF FINDINGS, CONCLUSIONS AND RECOMMENDTIONS

This chapter presents the summary of findings from the test conducted, conclusions

and recommendations drawn out from the collective data.

Summary of Findings:

The machine was tested for 6 different methods comprising of Standard Proctor

Test (Method A, B and C) and Modified Proctor Test (Method A, B and C) as specified by

American Society for Testing and Materials (ASTM). The following findings are obtained

from the test conducted:

Standard Proctor Test (Method A):

Mechanized Compaction provides a higher value of maximum dry density

of the soil (1.64 g/cm3) than the result of soils maximum dry density us ing Manual

Compaction (1.62 g/cm3)

Modified Proctor Test (Method A)

Using the same soil in Modified Proctor Test (Method A), Mechanized

Compaction still gives a higher value of maximum dry density (1.97 g/cm3) than

the maximum dry density (1.78 g/cm3) in Manual Compaction.

Standard Proctor Test (Method B)

The result of maximum dry density of the soil (1.73 g/cm3) in

Mechanized Compaction (Method B) indicated a higher compaction effort than

with the result of maximum dry density (1.64 g/cm3) in Manual Compaction.


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Modified Proctor Test (Method B)

Testing the same soil using Modified Proctor Test, the value of maximum

dry density (2.35 g/cm3) in Mechanized Compaction is still higher than the

maximum dry density (1.65 g/cm3) in Manual Compaction.

Standard Proctor Test (Method C)

Mechanized Compaction (Method C) provides a higher value of maximum

dry density of the soil (2.04 g/cm3) indicating a higher compaction effort as

compared to the Manual Compaction. (1.83 g/cm3).

Modified Proctor Test (Method C)

The value of maximum dry density of the soil (1.78 g/cm3) using

Mechanized Compaction is still higher than maximum dry density (1.73 g/cm3) in

Manual Compaction when tested with Modified Proctor Test.

Conclusion:

Based from the different methods and series of test conducted, the researchers came

up with the following conclusions:

1. The development of the Mechanized Soil Compactor has been efficient. It has been

proven by extensive testing in a laboratory that the machine can successfully

complete a soil compaction of a test specimen for Moisture-Density Relation Test

with a great level of assurance in the end result.

2. Comparing to manual method, it is much convenient to use the machine for this

type of laboratory test that requires laborious performance of the procedure.


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3. The consistent application of blows to the soil surface ensuring an equal

compaction distribution to the test specimen can also be achieved using the

machine.

4. By complying with the standards and specifications of ASTM, the machine is thus

suited to be used in every laboratory that conducts MDD and OMC test.

5. Based from the OMC and MDD results provided by the automated and manual

compaction, the machine has been proven that it produces higher compaction effort

than the manual compaction which indicates a better result of soil compaction.

6.

When compared to existing mechanized soil compactor, the time to finish the blows

(25 blows or 56 blows) using the newly fabricated machine is faster than the

machine used by Department of Public Works and Highways (DPWH), Region 3.

Recommendation:

To further improve the study, the following recommendations may be done:

1.

Although it is quite costly, it may be more efficient to use PLC system as the main

control box that will be used to control and give power to the whole machine for

future study

2. The number of tests could be increased to extend the ranges of moisture contents

and bulk densities to provide better insight on the surface soil displacement.

3. The researchers recommend to perform the test complying with the parameters set

by AASHTO Standards. In AASHTO, four methods are being introduced (Method

A, B, C and D) as compared to three methods specified by the ASTM Standards.

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