Div 04

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BUILDING TECHNOLOGY I
Div 04 MASONRY
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1. MORTARS AND PLASTERS
- a proportioned mixture of siliceous materials
(sand, crushed stone) and cement (lime, Portland)
which, after being prepared in a plastic state
with water, hardens into a stonelike mass.

• Mortar is cement mix used to glue masonry units
  to each other, or other surface finishing
  materials like tiles, bricks, stones to a
  receiving structure like a wall or floor.
• Plaster is mortar applied to wall surfaces as a
  preparation or a hard finish coat.

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1. MORTARS AND PLASTERS
1.01 CEMENT MORTAR

• is a proportioned mixture of cement, fine
  aggregate and water.
• For first-class mortars 1 part of cement should
  be added to not more than 3 parts of sand.
• Replacing 10 or 15 percent of the cement by
  volume with hydrated lime gives greater
  workability and increases the strength of the
  mortar.
• For rubble stonework, 1 4 will be much stronger
  than lime mortar.
• For the top surface of floors and walks, use 1
  1 to 1-1/2.
• Mortar made with fine sand requires a much larger
  quantity of cement to obtain a given strength
  than mortar made with coarse sand.

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1. MORTARS AND PLASTERS
1.01 CEMENT MORTAR
- Mortar may be mixed by hand or mechanical
mixers, the latter being preferred for large
quantities. - When the mixing is done by hand,
it should be done on platforms made watertight to
prevent the loss of cement. - The cement and
sand should be mixed dry in small batches in the
proportions required on a clean platform.
- Water is added and the whole remixed until it
is homogeneous in color and leaves the mixing hoe
clean when drawn out. - Mortar should never be
retempered after it has begun to set
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1. MORTARS AND PLASTERS
1.02 PLASTER

• is a mortar of cementitious material ( lime,
  gypsum or cement), sand and water which is
  applied in coats (layers) to masonry surfaces,
  lath or various types of plaster board to give a
  hard finish surface to interior or exterior walls
  and ceilings.
• the word plaster refers to gypsum plaster and
  the words gypsum and plaster are often used
  interchangeably.
• Fiber or hair is sometimes added to the mixture
  to give increased strength as when used for the
  first coat.
• Plastering is done according to two basic
  methods two-coat and three-coat. A three-coat
  job consists of

• a first binding coat called scratch coat
• a second straightening coat called the
  brown-coat and
• a final coat called the finish coat.

In the two-coat work, the scratch and brown coats
are combined into one.
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1. MORTARS AND PLASTERS
1.03 TYPES OF PLASTER AND THEIR USES
a. Lime Plaster
Lime putty (hydrated lime and water), mixed on
the job with sand and gypsum plaster, used for
two and three-coat finish surfaces for interior
walls and ceilings.
Scratch coat 1 part lime putty, 1 part
Portland cement or Keenes cement, 2-3/4 parts
sand by weight. Brown coat 1 part lime
putty, 1part Portland cement or Keenes cement, 3
parts sand by weight. Finish coat Hard
finish 1 part lime putty, 1/3 gypsum plaster
by volume Sand float 1 part lime putty, ¼
gypsum plaster, 2 parts sand by volume
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1. MORTARS AND PLASTERS
1.03 TYPES OF PLASTER AND THEIR USES
b. Gypsum Plaster

• Gypsum plaster. Plaster of Paris mixed with clay,
  lime and other materials in combinations covered
  by trademarks or patents. Mixed on the job with
  water, sand, lime putty, hair or fiber for two or
  three-coat finish surfaces for interior walls and
  ceilings or used dry as ingredient for hard or
  sand float finish with lime plaster (see above).
• High-strength gypsum plaster. Same as gypsum
  plaster but mixed to meet established standards.
  Mixed on the job with water, sand, lime putty,
  hair or fiber for two and three-coat finish
  surfaces for both exteriors and interiors.

• Scratch and brown coats 1 part high-strength
  gypsum plaster to 2 parts sand by weight.
• Hard finish ¼ lime putty to 1 part
  high- strength gypsum plaster by volume

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1. MORTARS AND PLASTERS
1.03 TYPES OF PLASTER AND THEIR USES
b. Gypsum Plaster

• Fibered gypsum plaster. Gypsum plaster premixed
  with fibers. Mixed on the job with water and sand
  for scratch coat for three-coat plastering job
• Prepared gypsum plaster. Gypsum plaster mixed
  with fine white sand. Used for two and three-coat
  finish surfaces for interior walls and ceilings .

• Scratch and brown coats mix per manufacturers
  instructions.
• Finish coat Any type of final coat plaster
  (gypsum, Keenes cement, lime or prepared
  finish coat

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1. MORTARS AND PLASTERS
1.03 TYPES OF PLASTER AND THEIR USES
b. Gypsum Plaster

• Bonding plaster. Gypsum plaster mixed with
  ingredients develop more adhesive strength in
  combinations covered by trademarks or patents.
  Used for interior finish for smooth concrete
  walls or ceilings. Mix and apply as per
  manufacturers directions
• Lightweight gypsum plaster, fire-resistant
  plaster. Gypsum plaster mixed on the job with
  water, perlite, vermiculite or other suitable
  mineral aggregate. Lightweight gypsum plaster is
  used when weight is important, and for
  fire-proofing other materials such as steel.
  Applied on lath. For interior use only .

• Scratch and brown coats 2 sand, 2 cu. ft.
  perlite or vermiculite per 100 lb. of plaster.
• Brown coat 3 sand, 3 cu ft. perlite or
  vermiculite per 100 lb. of plaster.
• Finish coat
• Hard finish 1/3 gypsum plaster, 1 lime
  putty by volume
• Sand Float Finish 1 gypsum plaster, 1-1/2
  sand by volume

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1. MORTARS AND PLASTERS
1.03 TYPES OF PLASTER AND THEIR USES
b. Gypsum Plaster

• Keenes cement. Plaster of Paris mixed with alum
  or borax or other materials and burned (calcined)
  at 932?F. Mixed on the job with water, lime putty
  and fine white sand as hard finish for two and
  three-coat gypsum plaster. For interior use only

• Hard finish 1 Keenes cement, ¼ lime putty,
  1/10 fine white sand by weight .
• Sand float finish ½ Keenes cement, 2 lime
  putty, 4 ½ sand by volume.

• Plaster of Paris. For ornamental plaster work and
  castings.
• Molding plaster. For ornamental plaster work and
  castings. Mix with water as per manufacturers
  directions.
• Acoustics plaster. For acoustic treatment of
  interior walls and ceilings. Applied on gypsum
  plaster base coats. Mix with water as per
  manufacturers directions.

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1. MORTARS AND PLASTERS
1.03 TYPES OF PLASTER AND THEIR USES
c. Portland Cement Plaster

• Mixed with water, sand and lime putty. Used for
  two and three-coat finish surfaces for exterior
  and interior walls and ceilings

• Scratch and brown coats 1 cement, ¼ lime
  putty, 3 sand.
• Sand float finish 1 cement, ¼ lime putty, 3
  sand.

• Thickness of plaster coats depends on the type of
  material to which the plaster is applied.
  Generally, the total thickness is 5/8 on metal
  lath and ½ on lathing board and gypsum block.
• In three-coat plastering work, the scratch and
  brown coats are ¼ thick at minimum the finish
  coat is 1/8 with a minimum of 1/16 at any
  point.
• For two-coat work, the base coat is ½ and the
  finish coat is the same as three-coat work.

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1. MORTARS AND PLASTERS
1.03 TYPES OF PLASTER AND THEIR USES
d. Sgraffito

• is highly decorative type of plaster work
  developed in Italy during the Renaissance. This
  type of technique consists of applying two or
  three thin coats of plaster different colors and
  then cutting away certain areas of one or two
  coats to produce a three-dimensional colored
  design.

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2. UNIT MASONRY
2.01 DEFINITION
Masonry - is a built-up construction or
combination of building materials as clay,
concrete, or stone set in mortar or plain
concrete.
Masonry Terms

1. Bed The horizontal surfaces on which the stones
   or bricks of walls lie in the courses.
2. Course A continuous layer of bricks, stones, or
   other masonry units
3. Wythe or Tier Each continuous, vertical section
   of the wall, one masonry unit thick.

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2. UNIT MASONRY
2.01 DEFINITION
Masonry Terms

1. Bond That connection between bricks, stones or
   other masonry units formed by lapping them one
   upon another carrying up the work, so as to form
   an inseparable mass of building, by preventing
   the vertical joints falling over each other (also
   called a breaking joint).
2. Stretcher A brick or block masonry laid
   lengthwise of a wall
3. Header A brick or block masonry extending over
   the thickness of the wall

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2. UNIT MASONRY
2.01 DEFINITION
Masonry Terms

1. Heading course A course in which the bricks or
   other masonry units are all headers.
2. Soldier A unit laid on its end with its face
   perpendicular to the face of the wall.
3. Quoins The corner stones at the angles of
   buildings, usually rusticated so as to project
   from the normal surface of the wall.
4. Bond Stones Stones running through the
   thickness of the wall at right angles to its
   face, in order to bind it together.
5. Blocking or Blocking Course A course of stones
   placed on top of cornice crowning the walls

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2. UNIT MASONRY
2.02 STONE

• Stone, together with wood and clay, are the basic
  building material of man. The history of
  architecture until as late as 1900 was largely
  the history of stone in architecture,

• Stone was the structural material, the exterior
  and interior finishing material, the flooring
  material and in many cases the roofing material.
• It was also used for all types of sculpture,
  statuary, and decorative and ornamental
  applications.
• Today, stone is largely used as a surface
  finishing material for both the exterior and
  interior of buildings.

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2. UNIT MASONRY
2.02 STONE

• Stone commonly used for architectural purposes
  include
• granite
• marble
• travertine

limestone sandstone slate.
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2. UNIT MASONRY
2.02 STONE
They are commonly classified as

1. Rubble Stone. Stone delivered from the quarries
   rough and irregular shape.
2. Dimension Stone. Stone cut into specific size,
   squared to dimensions, and to a specific
   thickness

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2. UNIT MASONRY
2.02 STONE

• STONEWORK The types of stonework are based on
  the shape and the surface treatment of finish of
  the stone

• Rubble work. Masonry of rough, undressed stones.
• When only the roughest irregularities are
  knocked off, it is called scabbled rubble, and
• when the stones in each course are rudely
  dressed to a nearly uniform height, range rubble
  .
• Random work. Stones fitted together at random
  without any attempt to lay them in course.

RUBBLE WORK
RANDOM WORK
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2. UNIT MASONRY
2.02 STONE

• STONEWORK

1. Ashlar. Squared stones in regular courses, in
   contradistinction to rubble work .

• Ranged work or coursed ashlar Uniform courses
  with stones uniform in size.
• Broken range ashlar Course laid with the
  horizontal joints uninterrupted but the width of
  the courses and the length of the stones are
  varied to produce a wall with a less regular
  pattern.

RANGED WORK
BROKEN RANGED WORK
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2. UNIT MASONRY
2.02 STONE

• STONEWORK

1. Ashlar

• Random course their rectangular shape and are
  laid on horizontal beds but no effort is made to
  continue the horizontal beds through in an
  uninterrupted manner. Large stones combine with
  small ones in a convenient and, if possible, an
  interesting manner.

RANDOM COURSE WORK

• Rustic or Rock work - Courses of stone face which
  is jagged, so as to present a rough surface.

RUSTIC OR ROCK WORK
Rustication occurs when heavier stones or
areas of stone project from the normal face of
the surrounding wall or of the joint themselves.
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2. UNIT MASONRY
2.03 BRICKS

• are structural units of clay or shale formed
  while plastic and subsequently fired.
• The manufacture of brick consists essentially of
  screening, grinding, or working the clay to the
  desired consistency for moulding, whether by hand
  or machine.
• After moulding, the bricks are dried and then
  burned in kilns for many hours at high
  temperatures, approximately 2000?F.
• These processes purify the raw products, make it
  uniform and homogeneous, burn out all combustible
  matter, and result in a product which is both
  stable and physically permanent .

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2. UNIT MASONRY
2.03 BRICKS
The types of bricks most frequently used in
architecture are

1. Common or building brick. Used for all purposes,
   including facing.
2. Facing brick. Specially processed to give certain
   specific surface characteristics. Used for
   exposed masonry surfaces.
3. Glazed brick. These have a smooth outer surface
   with a dull satin or high gloss finish. They are
   load bearing, fire resisting, and impervious.
   They are usually formed with vertical hollow
   cores through the body with scoring on the back.
4. Fire (refractory) brick. These are ordinarily
   made from a mixture of flint clay and plastic
   clay, and are used for the lining of furnaces,
   fireplaces, and chimneys.

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2. UNIT MASONRY
2.03 BRICKS
BRICK WORK. The usual methods of laying brick are
as follows

1. Common Bond. Consists of five stretcher courses
   and then a header course. It is generally begun
   with a row of headers at the bottom course
2. English Bond. Consists of alternate courses of
   stretchers and headers .
3. Flemish Bond. Consists of alternate headers and
   stretchers in each course .
4. Herringbone. The bricks are laid diagonally to
   form a herring-bone pattern.

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2. UNIT MASONRY
2.03 BRICKS
Mortar joints between brick courses are usually
from 4.5mm (3/16) to 12mm (½).
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2. UNIT MASONRY
2.04 CONCRETE HOLLOW BLOCK

• Concrete Hollow Block (CHB) is a hollow masonry
  unit, with two or three cells or cores, made of
  the following ingredients water, Portland
  cement, and various types of aggregate such as
  sand, gravel, and crushed stone.
• Lightweight concrete hollow blocks are also
  manufactured with such aggregates as cinders,
  expanded slag, expanded shale or clay. Expanded
  blast furnace slag rates the highest in fire
  resistance, and due to its cellular structure,
  has high sound and thermal insulation quality.
• These are manufactured by machine-mixing the
  ingredients, pouring the mix into molds, and
  curing the block by air drying. A
  steam-and-pressure curing process is also used
  which can produce concrete hollow block in a few
  hours.

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2. UNIT MASONRY
2.04 CONCRETE HOLLOW BLOCK

• Standard CHB sizes are from thicknesses of 100mm
  (4), 150mm (6) and 200mm (8) x height of 200mm
  (8) x length of 400mm (16).
• CHB of 100mm (4) thickness should be used only
  for interior partition walls where
  weather-tightness is not required.

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2. UNIT MASONRY
2.04 CONCRETE HOLLOW BLOCK

• The different types of concrete hollow block
  include

1. Beam or lintel blocks

• Stretchers
• Headers

1. Corner blocks
2. Jamb blocks

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2. UNIT MASONRY
2.04 CONCRETE HOLLOW BLOCK

• Concrete hollow blocks should be laid on a full
  bed of mortar with horizontal and vertical joints
  10mm (3/8) thick.
• Reinforcement for 100mm (4) and 150mm (6) thick
  wall shall be 10mm? vertical bars at 600mm on
  centers and 10mm? horizontal bars every third
  course.

• Reinforcement for 200mm (8) thick walls shall be
  12mm? vertical bars at 600mm on center and 12mm?
  horizontal bars every third course.
• All horizontal reinforcement shall be tied to the
  vertical reinforcement at their intersections.
• Dowel bars should be placed into the piers,
  columns, slabs, leaving 20 bar diameters exposed
  to splice with the reinforcement of the hollow
  blocks.

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2. UNIT MASONRY
2.04 CONCRETE HOLLOW BLOCK

• Block cells with reinforcement are filled with
  cement mortar.
• Concrete hollow block walls should have a
  reinforced concrete lintel or beam block course
  every twelfth course and a concrete column
  stiffener at every 4.80 meters length.

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2. UNIT MASONRY
2.05 DURISOL BLOCK

• DURISOL block is lightweight block made from
  fiber and cement.
• DURISOL block units are two-core, 100mm (4) or
  150mm ( 6) x 87mm (7-1/2) x 600mm (24).
• - Reinforcement shall be 10mm ? vertical bars at
  720mm (36) on center and at every 4th course.
  Every 4th course should be a beam block course.
  Cores shall be solidly filled with cement mortar.
  

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2. UNIT MASONRY
2.06 PLASTER BLOCK

• also known as gypsum partition blocks, are
  usually made of gypsum, vegetable fibers as
  binders, and reinforcement.
• used for lightweight, fire-resistant interior
  partitions and for furring and fireproofing
  columns.
• Gypsum hollow blocks are manufactured in units of
  75mm (3), 100mm (4) or 150mm ( 6) thicknesses,
  x 300mm (12) height x 700mm (30) length.
• Gypsum solid block is manufactured only with a
  50mm (2) thickness.

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2. UNIT MASONRY
2.07 STRUCTURAL CLAY TILE

• Structural clay tile are hollow masonry units,
  open at two ends with interior webs or partitions
  19mm (¾) to 25mm (1) dividing the block into
  longitudinal cells.
• In its manufacture, the various shapes of clay
  tile are formed through special dies and then
  wire-cut into the required lengths.
• It may have a smooth or scored (grooved) surface.
  Structural clay tile is classified into

1. Load-bearing wall tile. 300mm x 300mm x 300mm
   (12 x 12 x 12)
2. Non-load bearing, fireproofing, partition, and
   furring tile. 100mm (4) or 125mm (5) x 200mm x
   300mm

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End of Div 04 MASONRY