Lecture No. 3 - PowerPoint PPT Presentation


Title: Lecture No. 3


1
Lecture No. 3 4Sand and Gravel
  • Sand and Gravel According to the classification
    of Wentworth, 1922 sand is defined by materials
    ranging in size between 1/16 to 2 mm, and the
    coarser material is termed gravel. Both are
    subdivided and appropriate modifier are given to
    size grades of each (Fig. 1)

2
(No Transcript)
3
  • Uses of Sand and Gravel
  • 1- The construction and paving industries are the
    principle consumers of sand and gravel, the chief
    use of both materials being as aggregate in
    Portland cement concrete since concrete contain
    80 to 90 by weight.
  • 2- Sand and gravel without cement admixture is
    extensively used as base or sub grade materials
    for highway and airport.
  • 3- Minor amount is used in rail road ballast and
    fill and on unpaved roads.
  • 4- High silica sand is used in manufacture white
    glaze, and abrasive in mechanic this need size
    less than 200 meshes.
  • 5- Sand alone is used in both concrete and
    plaster.
  • 6- Sand and gravel of dunes and glacial lakes
    beds are worked for their content of detrital
    gold, cassiterite , ilmenite and other metallic
    minerals.
  • 7- Alluvial sand deposits used active materials
    for soil.

4
  • Properties of sand and gravel
  • 1- Sand and gravel are unconsolidated, highly
    variable mixture of many constituents.
  • 2- Sand and gravel are capable of being
    artificially up graded by such process as
    screening, washing and combining of size grades.
  • 3- Deposits used for aggregate must be clean that
    free of dirt mica, and organic matter. Clay if
    disseminated in quantity through out of the
    deposits minor amount that can be washed out. A
    large proportion of silt (materials passing the
    No. 200 sieve) is deleterious as most
    specification either allows no silt or maximum of
    only 5 .
  • 4- Coatings of clay, calcium carbonate, iron
    oxide, or other substances on particles are
    undesirable, because the bond between particles
    and coating may be weak and this weakness the
    bond with the cement paste.
  • 5- In addition, some coating become chemically
    unstable in the concretes as it hardens and cures.

5
  • 6- Resistance to abrasion is important in the
    processing of aggregate and also in application
    in concrete especially those used for paving.
  • 7- Deposits of gravel are capable if chiefly
    composed of hard rock type such as vein quartz,
    quartzite fresh granitic rocks and dense non
    clayey limestone and dolomite.
  • 8- Chert, thought it may be hard and coherent in
    undesirable because of its tendency to react
    chemically with the cement paste.
  • 9- Soundness is also important. Good aggregate
    must have resistance to freezing and thawing and
    to wetting and drying. Therefore, fractured and
    porous fragments can not be accepted, as they may
    split, flake, or crack in the concrete.
  • 10-The deposits of sand and gravel it is
    necessary that have a wide particle size range
    from coarse gravel to fine sand. An excess of
    coarse materials may mean crushing it to size,
    too much fine and may result in wastage of finer
    proportion

6
  • 11- Another factor, particle shape,
    equidimensional, rounded particle are preferred,
    as angular fragment make harsh concrete that is
    difficult to work. Flat or elongated particles,
    besides decreasing workability, tend to orient
    themselves horizontally in the concrete, allowing
    water to accumulate beneath them and preventing
    the development of a good cement-aggregate bond
    on their lower surface.
  • 12- Sand and gravel must include specific gravity
    elasticity, compressibility, and thermal
    conductivity.
  • Alkali aggregate reactivity

7
  • Special uses of sand
  • 1- Glass sand
  • -Ordinary glass industries Qtz 93
  • -Optical glass industries Qtz 99
  • Impurity in glass sand effect the on color
  • Iron oxides must be not exceed 0.06, Cr, Co, not
    exceed 0.0002
  • Cu produced red or blue color
  • Cobalt- produced blue color
  • Ni Mg produced purple or brown
  • Ti produced brown color
  • Raw materials for Glass industries
  • 52-62 quartz
  • Soda ash (Na2CO3)
  • Lime (CaO)

8
  • 2-Foundary sand
  • Used for
  • Molding sand
  • Core sand
  • The sand that are used as foundry sand must be
    contain these properties
  • Sufficient cohesiveness
  • Sufficient refractoriness
  • Sufficient Strength
  • Enough permeability
  • Proper texture and composition

9
  • 3-Fracturing Sand
  • A method of treating pay zone in oil and gas
    wells was developed in 1949.Afluid with sand in
    suspension is pumped rapidly down the well casing
    under high pressure in to the oil gas bearing
    rock this is cause
  • 1- Enlarge existing opining
  • 2- Creating new fractures increasing the
    permeability and allowing grater flow of oil and
    gas toward the well bore.
  • The type of sand used must be high silica
    drilling mud acid and preferably with no
    carbonate silicate, or other oxides

10
  • 4- Abrasive sand
  • A general term for quartz sandstone sowing glass
    grinding and metal polishing and also to clean
    casting, to remove paint rust and to carve
    designs on stone. Foremost all uses required
  • 1-Clean sand , 2- Hard sand 3- Tough grains 4-
    Angular grain because they cut faster.
  • 5-Fire Sand or Furnace Sand
  • It is used in building floors in acid open hearth
    furnaces and lining cupolas and idles that
    contain molten metal. The sand for this use must
    be
  • 1- Course sand 2- clayey naturally bonded sand
    may be used, or plastic fire clay may be added to
    wash sand

11
  • 6 -Filter Sand
  • Is used to remove sediment and bacteria from
    water supplies
  • this sand must be
  • 1- Free from lime, clay and organic matter
  • 2- Must be least 98 insoluble in Hcl
  • 3- Grain shape seems to make little differences
    but uniformity and size distribution of grains
    are important.
  • Special uses of gravel (Pebble)
  • Used in rail road ballast and pebble must be
    composed of rock
  • fragments (granite, basalt, hard limestone, well
    cemented
  • sandstone)

12
  • Road stone and Basalt
  • The surfacing of road (the uppermost layer) which
    rest on
  • base and sub base depend on
  • 1- Consist of crushed rocks of small grade size
    (chipping) with a bituminous binder.
  • 2- A road surface has to withstand abrasion and
    resist impact.
  • 3- The fragment should preferably be angular and
    with out oxidized coating on their surface.
  • 4- The polishing properties of the stone should
    be low.
  • 5- The crushed stone it self forms along part of
    surfacing and tests of physical properties have
    been used for many year (B.S ASTM) they include
    test for crushing strength
  • 1- Abrasion
  • 2- Impact attrition (Deval and Los anglest test)
    aggregate crushing strength.
  • 3- Water absorption.
  • 4- Polishing properties.
  • 5- Durability.

13
  • Sandstone
  • Classification of sandstone by Pettijohn, 1957
  • 1- Graywacke is sandstone with variable quartz
    content, generally less than 75 25 or more
    consist of
  • sand-size grains of rock and feldspar.
  • 2- Arkosic sandstone the grains are dominantly
    quartz and feldspar, and cement, if present, is a
    mineral precipitate. The verity with more than 25
    feldspar is arkose that with less is
    feldspathic sandstone.
  • 3- Lithic sandstone is applied when rock
    particles exceed feldspar the cement is a
    mineral precipitate.
  • 4- Subgraywake contains less than 75 quartz,
  • 5- Protoquartzite contain 75 to 95 quartz.
  • 6- Orthoquartzite, the grains are 95 or more
    quartz, cement is a mineral precipitate.

14
  • Uses of sandstone
  • 1- Dimension sandstone is used for exterior
    facing and trim on a large building for ashlars
    in residential constriction, as flagstone and
    curbstones, and bridge abutments and retaining
    walls.
  • 2- Protoquartzite and orthoquartizite are
    important as source of grindstone and sharpening
    stone
  • 3- Greywacke was used in thin slabs for paving
    and sidewalks.
  • 4- Well-cemented sandstone may be crushed and
    used for concrete aggregate railroad ballast.
  • 5- Largest proportion of commercial sandstone is
    weakly cemented and high in quartz, so that it
    can be disaggregated and utilized as source of
    molding sand
  • 6- Orthoquartizite is used as refractory stone or
    ganister (high-temperature silica brick.

15
  • 7- Pulverized quartz, some of which is made by
    grinding high-silica sand is used in manufacture
    of whiteware, glazes and porcelain enamel, as an
    inert filler or extender in paint, and as
    abrasive in machine soap and cleanser (fore
    these purpose it ground to minus 200-mesh, silt
    size and finer).
  • Properties of dimension sandstone
  • 1- The texture must be range from fine to
    coarse to be of value a given stone show only
    moderate range between these limits (pebbly bands
    and silty or shaly zone detract from appearance,
    workability and strength.
  • 2- The most desired color in sandstone are
    neutral shade or
  • grey in tan.
  • 3- Porosity in sandstone range from 2 to 15 or
    more. High porosity is undesirable, especially if
    pores are very small, because off damage from
    freezing and thawing.
  • 4- the crushing and transverse strength of
    well-cemented sandstone is more sufficient for
    all ordinary uses.
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Lecture No. 3

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Title: Lecture No. 3


1
Lecture No. 3 4Sand and Gravel
  • Sand and Gravel According to the classification
    of Wentworth, 1922 sand is defined by materials
    ranging in size between 1/16 to 2 mm, and the
    coarser material is termed gravel. Both are
    subdivided and appropriate modifier are given to
    size grades of each (Fig. 1)

2
(No Transcript)
3
  • Uses of Sand and Gravel
  • 1- The construction and paving industries are the
    principle consumers of sand and gravel, the chief
    use of both materials being as aggregate in
    Portland cement concrete since concrete contain
    80 to 90 by weight.
  • 2- Sand and gravel without cement admixture is
    extensively used as base or sub grade materials
    for highway and airport.
  • 3- Minor amount is used in rail road ballast and
    fill and on unpaved roads.
  • 4- High silica sand is used in manufacture white
    glaze, and abrasive in mechanic this need size
    less than 200 meshes.
  • 5- Sand alone is used in both concrete and
    plaster.
  • 6- Sand and gravel of dunes and glacial lakes
    beds are worked for their content of detrital
    gold, cassiterite , ilmenite and other metallic
    minerals.
  • 7- Alluvial sand deposits used active materials
    for soil.

4
  • Properties of sand and gravel
  • 1- Sand and gravel are unconsolidated, highly
    variable mixture of many constituents.
  • 2- Sand and gravel are capable of being
    artificially up graded by such process as
    screening, washing and combining of size grades.
  • 3- Deposits used for aggregate must be clean that
    free of dirt mica, and organic matter. Clay if
    disseminated in quantity through out of the
    deposits minor amount that can be washed out. A
    large proportion of silt (materials passing the
    No. 200 sieve) is deleterious as most
    specification either allows no silt or maximum of
    only 5 .
  • 4- Coatings of clay, calcium carbonate, iron
    oxide, or other substances on particles are
    undesirable, because the bond between particles
    and coating may be weak and this weakness the
    bond with the cement paste.
  • 5- In addition, some coating become chemically
    unstable in the concretes as it hardens and cures.

5
  • 6- Resistance to abrasion is important in the
    processing of aggregate and also in application
    in concrete especially those used for paving.
  • 7- Deposits of gravel are capable if chiefly
    composed of hard rock type such as vein quartz,
    quartzite fresh granitic rocks and dense non
    clayey limestone and dolomite.
  • 8- Chert, thought it may be hard and coherent in
    undesirable because of its tendency to react
    chemically with the cement paste.
  • 9- Soundness is also important. Good aggregate
    must have resistance to freezing and thawing and
    to wetting and drying. Therefore, fractured and
    porous fragments can not be accepted, as they may
    split, flake, or crack in the concrete.
  • 10-The deposits of sand and gravel it is
    necessary that have a wide particle size range
    from coarse gravel to fine sand. An excess of
    coarse materials may mean crushing it to size,
    too much fine and may result in wastage of finer
    proportion

6
  • 11- Another factor, particle shape,
    equidimensional, rounded particle are preferred,
    as angular fragment make harsh concrete that is
    difficult to work. Flat or elongated particles,
    besides decreasing workability, tend to orient
    themselves horizontally in the concrete, allowing
    water to accumulate beneath them and preventing
    the development of a good cement-aggregate bond
    on their lower surface.
  • 12- Sand and gravel must include specific gravity
    elasticity, compressibility, and thermal
    conductivity.
  • Alkali aggregate reactivity

7
  • Special uses of sand
  • 1- Glass sand
  • -Ordinary glass industries Qtz 93
  • -Optical glass industries Qtz 99
  • Impurity in glass sand effect the on color
  • Iron oxides must be not exceed 0.06, Cr, Co, not
    exceed 0.0002
  • Cu produced red or blue color
  • Cobalt- produced blue color
  • Ni Mg produced purple or brown
  • Ti produced brown color
  • Raw materials for Glass industries
  • 52-62 quartz
  • Soda ash (Na2CO3)
  • Lime (CaO)

8
  • 2-Foundary sand
  • Used for
  • Molding sand
  • Core sand
  • The sand that are used as foundry sand must be
    contain these properties
  • Sufficient cohesiveness
  • Sufficient refractoriness
  • Sufficient Strength
  • Enough permeability
  • Proper texture and composition

9
  • 3-Fracturing Sand
  • A method of treating pay zone in oil and gas
    wells was developed in 1949.Afluid with sand in
    suspension is pumped rapidly down the well casing
    under high pressure in to the oil gas bearing
    rock this is cause
  • 1- Enlarge existing opining
  • 2- Creating new fractures increasing the
    permeability and allowing grater flow of oil and
    gas toward the well bore.
  • The type of sand used must be high silica
    drilling mud acid and preferably with no
    carbonate silicate, or other oxides

10
  • 4- Abrasive sand
  • A general term for quartz sandstone sowing glass
    grinding and metal polishing and also to clean
    casting, to remove paint rust and to carve
    designs on stone. Foremost all uses required
  • 1-Clean sand , 2- Hard sand 3- Tough grains 4-
    Angular grain because they cut faster.
  • 5-Fire Sand or Furnace Sand
  • It is used in building floors in acid open hearth
    furnaces and lining cupolas and idles that
    contain molten metal. The sand for this use must
    be
  • 1- Course sand 2- clayey naturally bonded sand
    may be used, or plastic fire clay may be added to
    wash sand

11
  • 6 -Filter Sand
  • Is used to remove sediment and bacteria from
    water supplies
  • this sand must be
  • 1- Free from lime, clay and organic matter
  • 2- Must be least 98 insoluble in Hcl
  • 3- Grain shape seems to make little differences
    but uniformity and size distribution of grains
    are important.
  • Special uses of gravel (Pebble)
  • Used in rail road ballast and pebble must be
    composed of rock
  • fragments (granite, basalt, hard limestone, well
    cemented
  • sandstone)

12
  • Road stone and Basalt
  • The surfacing of road (the uppermost layer) which
    rest on
  • base and sub base depend on
  • 1- Consist of crushed rocks of small grade size
    (chipping) with a bituminous binder.
  • 2- A road surface has to withstand abrasion and
    resist impact.
  • 3- The fragment should preferably be angular and
    with out oxidized coating on their surface.
  • 4- The polishing properties of the stone should
    be low.
  • 5- The crushed stone it self forms along part of
    surfacing and tests of physical properties have
    been used for many year (B.S ASTM) they include
    test for crushing strength
  • 1- Abrasion
  • 2- Impact attrition (Deval and Los anglest test)
    aggregate crushing strength.
  • 3- Water absorption.
  • 4- Polishing properties.
  • 5- Durability.

13
  • Sandstone
  • Classification of sandstone by Pettijohn, 1957
  • 1- Graywacke is sandstone with variable quartz
    content, generally less than 75 25 or more
    consist of
  • sand-size grains of rock and feldspar.
  • 2- Arkosic sandstone the grains are dominantly
    quartz and feldspar, and cement, if present, is a
    mineral precipitate. The verity with more than 25
    feldspar is arkose that with less is
    feldspathic sandstone.
  • 3- Lithic sandstone is applied when rock
    particles exceed feldspar the cement is a
    mineral precipitate.
  • 4- Subgraywake contains less than 75 quartz,
  • 5- Protoquartzite contain 75 to 95 quartz.
  • 6- Orthoquartzite, the grains are 95 or more
    quartz, cement is a mineral precipitate.

14
  • Uses of sandstone
  • 1- Dimension sandstone is used for exterior
    facing and trim on a large building for ashlars
    in residential constriction, as flagstone and
    curbstones, and bridge abutments and retaining
    walls.
  • 2- Protoquartzite and orthoquartizite are
    important as source of grindstone and sharpening
    stone
  • 3- Greywacke was used in thin slabs for paving
    and sidewalks.
  • 4- Well-cemented sandstone may be crushed and
    used for concrete aggregate railroad ballast.
  • 5- Largest proportion of commercial sandstone is
    weakly cemented and high in quartz, so that it
    can be disaggregated and utilized as source of
    molding sand
  • 6- Orthoquartizite is used as refractory stone or
    ganister (high-temperature silica brick.

15
  • 7- Pulverized quartz, some of which is made by
    grinding high-silica sand is used in manufacture
    of whiteware, glazes and porcelain enamel, as an
    inert filler or extender in paint, and as
    abrasive in machine soap and cleanser (fore
    these purpose it ground to minus 200-mesh, silt
    size and finer).
  • Properties of dimension sandstone
  • 1- The texture must be range from fine to
    coarse to be of value a given stone show only
    moderate range between these limits (pebbly bands
    and silty or shaly zone detract from appearance,
    workability and strength.
  • 2- The most desired color in sandstone are
    neutral shade or
  • grey in tan.
  • 3- Porosity in sandstone range from 2 to 15 or
    more. High porosity is undesirable, especially if
    pores are very small, because off damage from
    freezing and thawing.
  • 4- the crushing and transverse strength of
    well-cemented sandstone is more sufficient for
    all ordinary uses.
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