Civil Engineering materials

1. Civil Engineering Materials

2. INTRODUCTION
• Building materials are those which are used for construction purposes such as bricks,
stones, timber, steel, clay, sand, cement etc.
• They have an important role to play in this modern age of technology as they contribute
in a nation’s economy and their output governs both the rate and the quality of
construction work.
• Factors which affect the choice of materials: climatic background and economic aspect
• Variety of requirements are placed on building materials: strength at low and high
temperatures, resistance to ordinary and sea water, interior decoration.

3. Building materials
Rock Materials:
●Compact rocks:Are stone blocks of differents
materials like limestone and granite that form
paving stones, flagstones,...
●Coarse aggregates: Particles greater than 4.75
mm.eg Gravel.
●Fine aggregates: Particles smaller than 4.75 mm
eg. Sand
●Clay: V
ery small grains that absorb water. Less
than 0.002 mm

4. Binders are materials that, if they are mixed
with water they become pasty. And whenthey
solidificate they adquire rigidity.
● Lime: It is obtained by the heating of
limestone. Used in masonry and decorative
finishes.
● Cement: It is the mostly used binder. There
are various kinds of cement: Ordinary
portland cement, Rapid hardening cement.
Used in masonry
● Gypsum: It is a mineral that is mixed with
water. It is used to make Plaster of Paris to
cover walls.

5. Concrete
● The concrete is a composite
combination of cement, sand,
coarse aggregate and water . A
ratio of 1:2:4 indicates one part
of cement, two parts of sand/fine
aggregate and four parts of
coarse aggregate.
● Reinforced concrete: It is a type
of concrete usually strengthened
with iron bars.
● Glass concrete: It is a type of
concrete made with recycled
glass. It has a better long term
strength and better thermal
insulation due to its better
thermal properties of the glass
aggregates.

6. Pottery Materials
● Pottery materials are pieces
fabricated with clay fired in a kiln.
● Bricks: These are pieces of firedclay.
A brick of standard size is 190mm x
90mm x 90mm (as per BIS). Used in
masonry.
● Stoneware: Stoneware is a vitreous
or semi-vitreous ceramic made
primarily from fire clay. Used to
make floors , walls, drainage pipes

7. ● Aluminum: Used in sides of
windows, doors...
● Woods: Used in roofs, doors,
windows, floors..

8. Properties of building materials
ii. Bulk density is the mass of a unit volume of material in its natural state with voids
denoted by kg/m3 .
iii. Specific gravity of solid particles of a material is the ratio of weight/mass of a given
volume of solids to the weight/mass of an equal volume of water at 4°C.
iv. Hygroscopicity is the property of a material to absorb water vapour from air. It is
influenced by air-temperature and relative humidity; pores—their types, number and
size, and by the nature of substance involved.
Material Density
Brick 2.5-2.8
Portland cement 2.6-2.9
Wood 1.5-1.6
Steel 7.8-7.9
i. Density is the mass of a unit volume of homogeneous material denoted by (g/cm3).
Table1

9. v. Water absorption denotes the ability of the material to absorb and retain water. It
is expressed as percentage in weight or of the volume of dry material.
vi. Fire resistance is the ability of a material to resist the action of high temperature
without any appreciable deformation and substantial loss of strength. Some of the
materials neither crack nor lose shape such as clay bricks, whereas some others
like steel suffer considerable deformation under the action of high temperature.
vii. Chemical resistance is the ability of a material to withstand the action of acids,
alkalis, sea, water and gases.
viii. Durability is the ability of a material to resist the combined effects of atmospheric
and weathering factors.