2.physical Properties of Materials

Civil Engineering Materials
Lecture No.02
Introduction to the Properties of

Materials
Prof.Dr.Tauha Hussain Ali / Engr.Masroor Ali Jatoi
08/01/22 1
Fair Use Notice
The material used in this presentation i.e., pictures/graphs/text,

etc. is solely intended for educational/teaching purpose, offered
free of cost to the students for use under special circumstances of
Online Education due to COVID-19 Lockdown situation and may
include copyrighted material - the use of which may not have been
specifically authorised by Copyright Owners. It’s application
constitutes Fair Use of any such copyrighted material as provided
in globally accepted law of many countries. The contents of
presentations are intended only for the attendees of the class
being conducted by the presenter.
PHYSICAL PROPERTIES OF
MATERIALS
08/01/22 3
Density
 It is the mass of a unit volume of
homogeneous material (excluding all the voids)
denoted by ρ .
It is the density of solid mass.
It is expressed in g/cm3
08/01/22 4
Bulk Density:
It is the mass of a unit volume of material in
its natural state (with pores and voids) denoted
by ρb .
It is expressed in kg/m3.
08/01/22 5
Density Index:
It is the ratio of bulk density to the density.
It is denoted by ρo .
It indicates the degree to which the volume of a

material is filled with solid matter.
 For almost all building materials ρo is less than
1.0 because there are no absolutely dense bodies in
nature.
08/01/22 6
Specific Weight:
It is also known as the unit weight.
It is the weight per unit volume of material
It is denoted by ϒ.
It is expressed in kilo-Newton/cubic meter
08/01/22 7
Specific Gravity:
Specific Gravity of solid particles of a material
is the ratio of mass of a given volume of solids
(density of solid) to the mass of an equal volume
of water (density of water) at 4°C.
It is denoted by Gs.
It has no unit since it is ratio of two similar
quantities
08/01/22 8
True or Absolute Specific Gravity:
If both the permeable and impermeable voids are
excluded to determine the true volume of solids, the
specific gravity is called true or absolute specific
gravity.
It is denoted by Ga.
It has no unit since it is ratio of two similar quantities
08/01/22 9
Apparent or Mass Specific Gravity:
If both the permeable and impermeable voids are included
to determine the true volume of solids, the specific gravity is
called apparent specific gravity.
It is denoted by Gm.
It is the ratio of mass density of material to the mass
density of water.
08/01/22 10
Porosity:
It is the degree to which volume of the material is
interspersed with pores.
It is denoted by n .
It is expressed as a ratio of the volume of pores to that
of the specimen.
08/01/22 11
Hygroscopicity:
It is the property of a material to absorb water
vapor from air.
It is influenced by air-temperature and relative
humidity; pores—their types, number and size,
and by the nature of substance involved.
08/01/22 12
Water Absorption:
It denotes the ability of the material to absorb
and retain water.
It is expressed as percentage.
The properties of building materials are
greatly influenced when saturated.
08/01/22 13
Weathering Resistance:
It is the ability of a material to endure (Bear)
alternate wet and dry conditions for a long
period without considerable deformation and
loss of mechanical strength.
08/01/22 14
Water Permeability:
It is the capacity of a material to allow water
to penetrate under pressure.
Materials like glass, steel and bitumen are
impervious.
08/01/22 15
Frost Resistance:
It denotes the ability of a water-saturated
material to endure repeated freezing and thawing
with considerable decrease of mechanical
strength.
Under such conditions the water contained by
the pores increases in volume even up to 9 per
cent on freezing.
Thus the walls of the pores experience
considerable stresses and may even fail.
08/01/22 16
Heat Conductivity:
It is the ability of a material to conduct heat.
It is influenced by nature of material, its
structure, porosity, character of pores and mean
temperature at which heat exchange takes place.
This property is of major concern for materials
used in the walls of heated buildings since it will
affect dwelling houses.
08/01/22 17
Thermal Capacity:
It is the property of a material to absorb heat
described by its specific heat.
Thermal capacity is of concern in the
calculation of thermal stability of walls of heated
buildings and heating of a material, e.g. for
concrete laying in winter.
08/01/22 18
Fire Resistance:
It is the ability of a material to resist the action
of high temperature without any appreciable
deformation and substantial loss of strength.
Fire resistive materials are those which char,
smolder, and ignite with difficulty when subjected
to fire or high temperatures for long period but
continue to burn or smolder only in the presence
of flame, e.g. wood impregnated with fire proofing
chemicals.
08/01/22 19
Refractoriness:
It denotes the ability of a material to withstand prolonged
action of high temperature without melting or losing shape.
Materials resisting prolonged temperatures of 1580°C or
more are known as refractory.
High-melting materials can withstand temperature from
1350–1580°C, whereas low-melting materials withstand
temperature below 1350°C.
08/01/22 20
Chemical Resistance :
It is the ability of a material to withstand the action of
acids, alkalis, sea water and gases.
Natural stone materials, e.g. limestone, marble and
dolomite are eroded even by weak acids.
Wood has low resistance to acids and alkalis.
Bitumen disintegrates under the action of alkali liquors.
08/01/22 21
Durability:
It is the ability of a material to resist the combined
effects of atmospheric and other factors.
08/01/22 22
Thank You
08/01/22 23

2.physical Properties of Materials

Uploaded by

Copyright:

Available Formats

2.physical Properties of Materials

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

2.physical Properties of Materials

Uploaded by

Copyright:

Available Formats

Civil Engineering Materials

Introduction to the Properties of

Prof.Dr.Tauha Hussain Ali / Engr.Masroor Ali Jatoi

The material used in this presentation i.e., pictures/graphs/text,

It indicates the degree to which the volume of a

Bitumen disintegrates under the action of alkali liquors.

You might also like