Construction Materials and Engineering - Module III - Lecture Notes

Construction Materials
and Engineering
Module - III
Shamjith Km
shamjithkeyem@gmail.com
Department of Civil Engineering
Government Polytechnic College Manjeri

Construction Technology
Masonry
Modern methods of constructions
Damp proof courses
Pre stressed concrete
Form work
Scaffolding, Shoring and Under pinning
Plastering and Pointing

Masonry
Art of building the structure using
stones, bricks, or concrete blocks.
Stone  Stone masonry
Brick  Brick masonry
Cement mortar or grout holds the
masonry units together.

Classification of masonry walls
1 Load bearing walls
2 Non-load bearing walls
3 Retaining walls
1) Based on load action

Load Bearing walls1
Walls which carries loads coming above it
If beams and columns are not used, load from roof
and floors are transferred to foundation by walls
Eg:- Normal house walls
Provides structural support
Thick walls (Occupy larger area)
Good quality stones or bricks
should be used

Non-load Bearing walls2
Walls which does not carry loads coming above it
If beams and columns are used, load from roof and floors
are transferred to foundation through this frame
These walls only support themselves and the weight of
the claddings attached.
Eg:- Walls in framed buildings, partition walls
Provides no structural support
Thin walls (Occupy less area)

Retaining walls3
Wall which holds or retains soil behind it
Helps to maintain ground surface at different levels
Provides safe space at lower portion
Prevents soil sliding

Classification of masonry walls
1 Stone masonry
2 Brick masonry
3 Laterite masonry
2) Based on material used
3 Composite masonry

Stone masonry1
Systematic arrangement of laying the stones and
bonding together with mortar to form a solid mass
Materials required: 1) Stones 2) Mortar

Brick masonry2
Systematic arrangement of laying the bricks and
Materials required: 1) Bricks 2) Mortar

Laterite masonry3
Systematic arrangement of laying the laterite and
Materials required: 1) Laterite 2) Mortar

Composite masonry4
Systematic arrangement of laying different types
of materials and bonding together them with
mortar to form a solid mass

Selection of stone for stone masonry:
1 Availability
2 Ease of working
3 Appearance
4 Strength and stability
5 Polishing characteristics
6 Economy
7 Durability

Technical terms
1 Natural bed
The plane along which the stone can be easily split
Direction of bed should be perpendicular to dirn of loading
2 Sill
Bottom surface of a door or window
3 Corbel
Projecting stone provided to support beam or wall plate

Technical terms
4 Course
A layer of stones or bricks
5 Cornice
Course of stone provided at top of wall
6 Coping
Course provided at top of wall to
protect the wall from rain water.

Technical terms
7 Spalls
Chips of stones used to fill up the empty spaces in masonry
8 Quoins
External corners or angles of a wall surface
9 Bond
Arrangement of layers by which no vertical joints
are formed

Different types of stone masonry
Rubble masonry Ashlar masonry
1. Coursed rubble
2. Uncoursed rubble
3. Random rubble
4. Dry rubble
5. Polygonal rubble
6. Flint rubble
1. Ashlar fine
2. Ashlar rough tooled
3. Ashlar rock (Quarry faced)
4. Ashlar chamfered
5. Ashlar block-in-course

Rubble masonry
Stones of irregular sizes are used
Quarry stones with slight modifications are used
Strength of rubble masonry depends on
1. Quality of mortar
2. Use of long through stones at frequent intervals
3. Proper workmanship (filling of mortar)
Rough or undressed stones can be used
Wider joints as stones are of irregular sizes

Dry rubble masonry4
No mortar used to join

Ashlar masonry
Built from accurately dressed stones
Uniform and fine joints of about 3 mm thickness
Height of courses = 30 cm
Costly
Used in basements, bridge piers, abutments, etc

Ashlar fine
All sides and faces of the block are finely dressed with chisel
Ashlar rough
Bed and sides are finely dressed.
Ashlar quarry faced
If exposed faces remain undressed
Ashlar Chamfered
If exposed faces rounded /bevelled at 45o angle

General principles and specifications
1 Should satisfy requirements of IS specifications
2 Stones should be hard, tough and durable
3 Colour of the stone should be uniform
4 All stones should be laid with their natural bed
5 Stones should be well watered before use
6 Dress according to specification of the work
7 Formation of continuous vertical should be avoided
8 Good quality mortar should be used
8 Chips and broken pieces should not be used

Brick Masonry
Brick
Standard size = 19 x 9 x 9 cm
Nominal size = 20 x 10 x 10 cm
(Including mortar thickness)
1 m3 B.W = 500 Nos
Average weight of a brick = 3.5 kg

Technical terms
1 Stretcher
Brick laid with its length parallel to the face of wall
2 Header
Brick laid with its length perpendicular to the face of wall
9
19
9
9
Stretcher face Header
face

3 Bed
Lower surface of the brick when laid flat
4 Bed joint
Horizontal layer of mortar upon which the bricks are laid
5 Arrises
Edges formed by the intersection of plane surfaces
of the brick
No.of arrises = no.of edges = 12

6 Perpends
Vertical joints separating the bricks in either
transverse or longitudinal direction
longitudinal direction
Transversedirection
Plan view

7 Lap
Horizontal distance b/w the vertical joints in
successive courses.
Lap
Perpends
Min lap length =
𝟏
𝟒
x brick length

8 Closer
Obtained by cutting a brick lengthwise
A) Queen closer
Queen closer
Queen Closer is placed
1) To avoid continuous vertical joints
2) To close a wall in some length

8 Closer
Obtained by cutting a triangular portion of brick such
that half width and half length.
B) King closer
King closer
King closer is used near doors and windows

8 Closer
Half width and full length is cutted
C) Bevelled closer
Bevelled closer
Used for splayed brick works

8 Closer
Full width cutting with 45o/60o with length
D) Mitred closer
Queen closer
Used at corners and junctions
45o/60o
45o/60o

9 Bat
Cutting the brick across its length
No
𝟏
𝟒
brick bat  Waste/used as aggregates
Half bat or 𝟏
𝟐
bat
𝟑
𝟒
bat

10 Raking back
A wall terminated in stepped fashion
Easy for future working, good appearence

11 Toothing
A wall terminated in such a way that alternate
courses are projected

12 Frog
Depression/projection to act as a key to hold the mortar
Prevent sliding of brick
Depth about 10 mm to 20 mm

13 Quoin
Heavier bricks laid at external corners

14 Bullnose
Brick moulded with a rounded angle
Used for rounded quoin

15 Cownose
Brick moulded with a double bullnose on end

Brick bonds
Method of arranging bricks in masonry so that
they overlap properly and are tied to act as a
single unit is called bond.

Different types of bonds
1 Stretcher bond
2 Header bond
3 English bond
4 Flemish bond
5 Garden-wall bond
6 Raking bond
7 Dutch bond
8 Brick-on-edge bond
9 English cross bond
10 Facing bond
A) English garden wall bond
B) Flemish garden wall bond
(Scotch bond/sussex bond)
A) Diagonal bond
B) Herring bone bond
C) Zigzag bond

Stretcher bond1
All bricks are laid parallel to wall face
Useful for one brick partition wall
Minimum thickness = 10 cm

Header bond2
All bricks are laid perpendicular to wall face
Used to lay curved walls (eg: well)
Minimum thickness = 20 cm
¾ bat
¾ bat

English bond3
Alternate courses consist of stretchers and headers
Strongest bond
H
S S S S
H H H H H H
H
S S S S
H H H H H HQueen closer
Quoin
header
Quoin stretcher

English bond3
In every header course, a queen closer is placed
next to a quoin header.
Each alternate header is centrally supported
over a stretcher.
Number of mortar joints in the header course is
nearly double than that in stretcher course

Flemish bond4
In every course headers and stretchers are placed
alternately.
Good appearance
SH
Queen closer
Quoin header
Quoin
stretcher
SH
S SH H
SH SH
S SH H

Queen closer is placed next to a quoin header in
every alternate course.
Every header is centrally
supported over a stretcher.
Types of Flemish bond:
1) Single Flemish bond
2) Double Flemish bond
Flemish bond4

One face only flemish bond,
other face English bond
Flemish bond4
Single flemish bond Double flemish bond
Both faces flemish bond
English bond
Flemish bond
Front
Back
Good in strength Good in appearence
Flemish bond
Flemish bond
Front
Back

Garden wall bond5
Used for garden works - importance to appearance
Maximum height = 2 m
Less strength – can’t use to take loads

Raking bond6
A) Diagonal bond C) Zig Zag bondB) Herring bone bond
One-sided diagonal Two-sided diagonal
Eg:- paving of bricks
Bricks placed in a
zig-zag manner

Brick should conform to IS Specifications
Specification for brick masonry
1
Bricks should be immersed in water for a sufficient time to
avoid them from absorbing water from the mortar
2
Brick should be laid on their beds with the frogs upward3
4 Brick bats should be avoided as far as possible
5 Maximum height of construction/day is 1.5 m
6 Joint thickness should be thin
Wall should be raised uniformly7
Good quality mortar & proper bonding should be confirmed8

Hollow block masonry
Concrete rectangular blocks made using light
weight aggregates.
Can be used for load baring and non-load bearing
members.

Advantages of hollow bricks
Available in regular and uniform size
Light in weight – can handle easily – faster
construction
As block is hollow, there is saving of material
As blocks are larger than bricks, number of joints
are less. Hence saving of mortar.
Rough surface makes plastering easier.
Can withstand high temperature – fire protection
Rapid execution of work

Types of hollow bricks
Stretcher Blocks1
Laid with length parallel to
the face of the wall
Corner Blocks2
used at the ends or corners
of masonry – doors/window
openings

Pillar Blocks3
used when two ends of the
corner are visible
Jamb Blocks4
used to provide space for
casing members of window

Partition Block5
Used to build partition walls
Lintel Blocks6
used for purpose of provision
of beam or lintel beam

Frogged Brick Blocks7
frog will help the block to
hold mortar and to develop
the strong bond
Bullnose Block8
When rounded edges are
needed at corners

Solid block masonry
Heavy in weight
Manufactured from dense aggregates
Strong – provide stability to structure
Used for load bearing walls
Available in large sizes compared to bricks
Regular size and uniform shape
Faster construction

Interlocking brick masonry
Solid blocks having a projection and depression so
that they can join together to form a single unit
Projection of one block fit into the depression of
the next so that they always align perfectly.
Holes provided to reduce amount of materials
Steel mesh can be used to increase strength
Permits water to seep into earth through joints
Faster construction and nice appearance
Available in different colours and regular sizes

Partition walls
Wall constructed inside the enclosed area
It separates various rooms in a building
Generally a non-load bearing wall
May be upto full floor height/eye level
Minimum thickness = 10 cm (Stretcher bond)

Requirements of partition wall
Strong enough to carry its own weight
Should be capable of resisting impact
Should act as a sound barrier when divides rooms
Should be light weight and thin
Should be cheap and easy for construction
Also need to carry fixtures, fittings and plasterings
Should be resistant to fire

Types of partition walls
1 Brick partitions
2 Clay block partitions
3 Concrete partitions
4 Glass partitions
5 Timber partitions
6 Metal partitions
7 Plaster slab partitions
8
Asbestos cement sheet
partitions
9 Strawboard partitions
10
Wood wool slab partitions

Modern methods of construction
Framed construction
Prefabricated construction
Earthquake resistant construction
1
2
3

Framed construction1
Frame is a network of footings, columns,
beams and slabs
Walls constructed within this frame
are called as panel walls
Whole weight of the structure is
transmitted to foundation through
this frame.

Advantages of framed construction
Thin panels – increases floor area
Greater freedom in planning
Partition walls can be changed when necessary
Better resistant to vibrations
Can be used for unreliable soils – piling, etc
Speed in construction
Resistant to earthquake
Suitable for any number of stories

Prefabricated construction2
Also known as modular construction
Structural components are manufactured in plants
which are away from building site
Transported to site and then assemble the parts.
Can manufacture large quantity of components in
less time period.

Advantages of prefabricated construction
Can erect the structure faster
Equipment and machinery need not transported
Plant casting allows increased efficiency, quality
control and greater control on finishes
Less affected by climatic factors
Division and specialization of human workforce
Saving of time and labour
Suitable for any number of stories
Reduced wastage of materials

Earth quake resistant construction3
Construction in which it can resist sudden
unpredictable ground shakings
Effects of earthquake
1. Ground shake
2. Landslides
3. Ground displacement
4. Liquefaction
5. Tsunami
6. Aftershocks

1 Continuity should establish in case of additions and alterations
2 Suspended ceilings should be avoided
3 Continuity of construction should be maintained
4 Structure should rest on strong foundations
5 Should provide suitable gap b/w adjoining structures
6 Connections b/w structural & non structural parts need smooth
7 Projections should be avoided as far as possible
8 Proper structural design should be done
9 Better to have light weight structures
8 Symmetrical shaped structures are good10
Requirements of earthquake resistant construction

Damp Proof Courses (DPC)
Dampness is the presence of hygroscopic or
gravitational moisture
Building should remain dry and free from moisture
Dampness reduces strength
Dampness give un-hygienic conditions
Provision of DPC prevent entry of moisture from
walls, floors and basement of a building

Rising of moisture from the ground
Action of rain
Exposed tops of walls – eg:- parapet, roofs
1
2
3
Condensation – eg: badly designed kitchen
Inadequate roof slope
Defective junctions – b/w parapet wall & roof slab
4
5
6
Causes of dampness

1 Causes rotting of wood
2 Causes corrosion of metallic fixtures
3 Deteriorate electric installations
4 Deteriorate carpet & furniture’s
5 Causes spots on the floors and walls
6 Causes petting off and removal of plaster
7 Causes bleaching and blistering of paints
8 Causes efflorescence in bricks, tiles and stones
9 Dangerous for the health of occupants
8 Promotes growth of termites  durability decreases10
Effects of dampness

8 Dampness give rise to breeding of mosquitoes11
Effects of dampness
8 Wall decorations and paints may damaged12
8 Flooring gets loosened due to reduction in adhesion13
8 Electrical fittings get damaged14
8 Floor coverings are damaged15

Use of DPC
Integral Damp proofing
Surface treatment
1
2
3
Cavity wall construction
Guniting
Pressure guniting
4
5
6
Methods of Damp proofing

Use of DPC1
Provide DPC b/w source of dampness & part of
building adjacent to it
Materials used :
1. Hot bitumen
2. Cement concrete
3. Plastic sheet
4. Mastic asphalt
5. Metal sheets
6. Stones and bricks

Integral Damp proofing2
Adding certain water proofing compounds to the
concrete mix so that it becomes impermeable
Materials used :
1. Publo
2. Permo
3. Silca
4. Snowcem
5. Dr.Fixit

Surface treatment3
Application of layer of water repellent substances
on the surface through which moisture enters
Materials used :
1. Calcium and Aluminium Oletes
2. Stearates
Pointing & Plastering of the exposed surfaces :
1. Sodium or Potassium silicates
2. Aluminum or Zinc Sulphates

Cavity wall Construction4
Main wall is shielded by an outer skin wall
(water repellent) leaving a cavity b/w the two

Guniting5
Depositing layer of rich cement mortar by pressure
to the exposed surface of walls, pipes, etc.
Mortar is shot on clean surface

Pressure Guniting6
Cement grout is filled in cracks, voids in the
structure of building by high pressure
This method is effective to control entry of ground
water through foundations.

Concrete and steel
Concrete is strong in compressions and
weak in tension
Steel is strong in both tension and compression

Pre-stressed concrete
A method to overcome concrete’s natural weakness
in tension.
Used to produce beams, floors or bridges with
longer span than with ordinary reinforced
concrete.

Principle of pre stressing
An initial load is applied on the structure
prior to its use (Like stretching an rubber band and holding
inside our hands, then release)
Process of induction of compressive stresses in the
structure before it is put to its actual use is known
as Prestressing

1) RCC – Reinforced cement concrete
2) PCC – Prestressed cement concrete

External or internal pre-stressing
Based on type of structure
1
2
Based on method of applying pre-stress
Source of prestressing
3
4
Types of prestressing
1. Linear prestressing
2. Circular prestressing
1. Pre tensioning
2. Post tensioning
1. Mechanical
2. Hydraulic
3. Electrical
4. Chemical

External prestressing
When pre-stressing
achieved by elements
outside the concrete.
Tendons lied outside
the member

Internal prestressing
When pre-stressing
achieved by elements
inside the concrete.
Tendons lies inside the
member

Pre tensioning
The tension is applied to the tendons before casting
the concrete
After hardening of concrete, tendon cuts, the tension
force is released.
The tendon tries to shrink back to its original length
Concrete resists this shrinking through bond b/w
concrete and tendon.
Compressive force is induced in concrete
Eg: - Electric poles, railway sleepers

Post tensioning
The tension is applied to the tendons (located in a
duct) after hardening of the concrete.
Ducts are placed inside the concrete before casting.
After the concrete gets hardened, the tendon inside
the duct is tied and anchored against concrete.
Eg: - box girders

1 Section remains uncracked under service loads
2 High span-to-depth ratios
3 Suitable for precast construction
4 Rapid construction
5 Better quality control
6 Reduced maintenance
7 Suitable for repetitive construction
8 Reduction of formwork
9 Availability of standard shapes
Advantage of prestressing

1 Prestressing needs skilled technology
2 The use of high strength materials is costly
3 There is additional cost in auxiliary equipments
4 There is need for quality control and inspection
5 Skilled labour needed
Limitations of prestressing

Formwork
When concrete is placed, it is in a plastic state
An artificial temporary support provided below and
around the concrete to hold the fresh concrete in
desired shape.

Formwork materials
Commonly made of wood and steel.
Plastics and fibers are also used.

Process involved
Assembly and
erection
Concrete
placement
Stripping and
dismantling

1 Serves as mould for concrete structural components
2 Decides accuracy to size, strength and surface finish
3 Holds the self weight of the fresh R.C.C
4 Provides a working platform
5 To support the weight
of concrete
Functions of formwork

1 Easy removal with least amount of hammering
2 Economy-Materials should be cheap and reusable
3 Water proof - Less leakage through the joints
4 Quality-desired size,shape,&finish need to obtained
5 Rigidity against deformations
6 Inside surface of formwork should be Smooth
7 Sufficient Strength to bear DL, LL, labour, etc.
8 Swelling and shrinkage should be minimum
Requirements of good formwork

Modern day formworks
1. Modular construction is used mainly
2. Fast and efficient
3. minimize wastage of concrete
4. Slip form technology used.

Slip form technology
A kind of mechanical formwork system suitable for use in
casting continual walls of structures.
Types of slip form:
1) Horizontal slip form
2) Vertical slip form
3) Tapered slip form
Lifting equipments are used to rise the slip form
Eg:- Large towers, canals, Chimneys
Also called as climbing forms and sliding forms

PVC forms
Available in standard sizes
Good in appearance
Easy to assemble and dismantle
Materials will not stick on it
Sufficient water proofing
Made of Polyvinyl chloride
Light in weight
Useful in case of high rise buildings

Scaffolding
To safely support men and materials
Temporary elevated platform
When height of construction/repair > 1.5 m
Usually made of timber/steel

1 Single (bricklayers/putlog) scaffolding
2 Double (masons) scaffolding
3 Cantilever (needle) scaffolding
4 Suspended scaffolding
5 Trestle scaffolding
6 Steel scaffolding
7 Patented scaffolding
Types of scaffold

Single scaffolding1
Wall
Standards
putlog
putlog
Toeboard
Toeboard
Ledgers
Guard rail
hole
Raker

Single scaffolding1
Used mainly for brick works
Also called as bricklayers or putlog scaffolding
Can’t use for plastering and painting

Technical terms
1 Standards – Vertical members of scaffold
2 Ledgers – Horizontal members parallel to wall
3 Putlog – supports on ledger and hole in wall
4 Toeboard – to provide working space for workers
5 Guard rail – to protect workers from falling
6 Raker – inclined support to scaffold
7 Transom – Putlogs, but both ends supported on ledgers

Double scaffolding2
transom
transom
(Putlogs, but both ends
supported on ledgers)

Double scaffolding2
Used mainly for plastering and painting
Also called as masons or independent scaffolding
Used for heavy works
Two standards will be present

Shoring
To support an unsafe structure
Temporary supporting structure
When addition and alterations need to
done on unsafe structures
Types of shoring
1. Raking (inclined) shores
2. Flying (horizontal) shores
3. Dead (vertical) shores

Shoring
This is used when stability of structure is endangered due to
Timber , RCC, or steel materials are used
1. Removal of a defective portion of structure
2. Unequal settlement during construction
3. To insert underground pipelines

Raking shores1
Wall plate
Needle
Cleat
Ride raker
Raker
Hoop iron wire
Sole plate
Unsafe buildingBraces

Fly shore2
Unsafe buildingSafe building Fly beam
Wedge
Straining piece

Underpinning
Placing of a new foundation below an existing foundation
Process of strengthening existing foundation

Underpinning is used in below conditions
1. When a building with deep foundation is constructed
near a building with shallow foundation. (shallow
foundation should be strengthened)
2. To protect from excessive settlement of foundation
3. To improve bearing capacity of soils
4. To provide basement to an existing structure

Plastering
Tools used:
Normal thickness = 12 mm
Gauging trowel, Float, Floating rule, Plumb bob
Coats in plastering
1. Rendering coat
2. Floating coat
3. Setting/finishing coat

1 Plastering removes unevenness of surfaces
2 Make surface smooth and clean
3 To develop decorative effects
4 To hide defective workmanship
5 To protect from dust
6 To protect surface against vermin
7 To protect from water penetration
Objectives of Plastering

Defects in plastering
Blistering
Small patches swell out beyond the plane of
plastered surface.

Cracks
Cracks get developed on
plastered surface

Efflorescence
While drying, soluble salts comes out and
appear as crystalline white substance.

Flaking
Formation of very small loose mass on
plastered surface.

Peeling
Plaster from some portion of surface comes out
and a patch is formed.

Popping/blowing
Conical hole formed Infront of plastered surface
due to particle which expand on being set.

Rust stains
Rust stains occur on certain plastered surfaces.

Softness
Some portion of plastered surface become soft.
Uneven surface
The surface become uneven after plastering.
Different thickness at different locations.

Pointing
For good strength (primary) and appearance
Action of filling joints of masonry with rich mortar
These spaces are filled up by suitable mortar in the
decided shape
Joints are raked out to a depth of about 20 mm
Mortar used for pointing: L.M or C.M in 1:1 or 1:2

Types of pointing
Flush pointing1
Recessed pointing2
Grooved pointing3
4 Tuck pointing
5 Struck pointing
6 V-pointing
Weathered pointing7
Beaded pointing8

Flush pointing1
20 mm
Old mortar
Rich Mortar
1:1 or 1:2
Recessed pointing2
Face of pointing is vertical
20 mm
Old mortar
Rich Mortar
1:1 or 1:2
Channel shaped appearance
5 mm back from face

Grooved pointing3
20 mm
Old mortar
Tuck pointing4
Rubbed or keyed pointing
20 mm
Old mortar
Rich Mortar
1:1 or 1:2
3 mm projection from face
5 mm back from faceSemi-circular depression
inwards at mid height
groove

Struck pointing5
10 mm
Old mortar
V - pointing6
20 mm
Old mortar
Rich Mortar
1:1 or 1:2

Weathered pointing7
Old mortar
Beaded pointing8
20 mm
Old mortar
Rich Mortar
1:1 or 1:2
To drain water easily

1 Cement mortar and lime mortar
2 Acoustic plaster – for sound treatments
3 Asbestos cement plaster
4 Barium plaster – to prevent radiation
5 Granite silicon plaster
6 Gypsum plaster – white colour
7 Keen’s cement (Plaster of paris + Alum)
8 Martin’s cement (Plaster of paris + pearl ash)
9 Parian cement (Plaster of paris + borax)
Materials for pointing
10 Sirapite (Plaster of paris + petroleum)

Construction Materials and Engineering - Module III - Lecture Notes

Construction Materials and Engineering - Module III - Lecture Notes

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Construction Materials and Engineering - Module III - Lecture Notes

Similar to Construction Materials and Engineering - Module III - Lecture Notes (20)

More from SHAMJITH KM

More from SHAMJITH KM (20)

Recently uploaded

Recently uploaded (20)

Construction Materials and Engineering - Module III - Lecture Notes

Editor's Notes