1. mylearnings.in
CIVIL ENGINEERING BASICS
For all competitive exams and for practicing engineers
What are Civil Engineering Basics ?
Civil Engineering basics are the basic parameters related to different Structures which all the
engineers should know.
Sub-structure :- Part of structure which is below the ground level is called substructure
Super-structure :- Part of structure which is above ground level is super structure.
Elevation – It’s the view which we can see when we stand right in front of the structure on any of
the sides.
Plastering – A cement, sand and water mix applied on brick wall for smooth surface for painting.
Plinth level – The level on which the actual structure stands on.
Riser – The vertical height of single step.
Tread – The horizontal portion where we put our foot on which going on steps.
Going – The inclined portion of stairs.
Footing – The bottom most part of structure. These are categorized as Isolated footing,
combined footing, Raft etc.
Columns – The vertical members of structure .
Clear cover – It’s the clear distance maintained from concrete face up to face of the
reinforcement steel.
Effective depth – It is the distance from top of the concrete face upto the CG of reinforcement.
Singly reinforced section – A section of concrete member with reinforcement at only on tension
face.
Doubly reinforced section – A section of concrete member with reinforcement on both tension
and compression side.
2. mylearnings.in
Stirrups –Steel bent in closed shape of either Rectangular of circular shape. These are generally
to hold column bars in position and also effective in shear carrying capacity.
Cantilever beam – A beam with fixed support on one side and the other end is free.
Propped cantilever – A beam with fixed support on one side and other end is with pinned
support.
Pedestal – When Length of the member is less than 3 times in width then its called pedestal.
One way slab – When ratio of length to width is more than 2 its one way slab
Two way slab – When ration of length to width is less than or equal to 2 , its two way slab.
Slender column – when length to width ratio of column is more than 12 , then its slender
column
Plain cement concrete (PCC) – The cement concrete mix provided on the ground level over
which foundations, beams are constructed. This is simply a levelling surface.
Pile foundation – The foundation system with Pile i.e cylinder shaped reinforced concrete.
Generally preferred when soil is very weak.
Frog – A small Depression on top of brick. This is for proper bonding with other bricks.
Scaffolding – A temporary structure constructed during the construction when work needs to be
carried out at higher elevations.
Retaining wall – A wall constructed to retain earth.
Tension – A force acting on member and in the direction away from the structure. Imagine
pulling the rubber band with two fingers.
Compression – A force acting on member in the direction towards the structure. This is simple
download load acting on structure.
Stress – Ratio of force applied to its sectional area.
Strain – This is the ratio of change in length to its original length.
Hooke’s Law – With in elastic limit stress is directly proportional to strain.
Poisson’s Ratio – It is the ratio of lateral strain to longitudinal strain.
Strut – A compression member in a truss.
Flab slab – A structural component supported only by columns and no beam arrangement.
Piers – The column types structures for supporting bridge slabs along the length.
3. mylearnings.in
Abutment – The end supports of bridge are abutments.
Lintel – A structural member just above the door or window or rolling shutter.
Cement :- Cement is basically obtained by grinding the stones containing lime and clay. Cement
is the binder which helps in the bonding of cement, sand along with water.
Some of the very important types of cement are
1. Low Heat cement used generally in construction of dams.
2. Sulphate resisting cement used in corrosive type environment. Ex. Sewage contact
surfaces
3. Rapid hardening cement
4. Quick setting cement
Aggregates : - Aggregates are generally of two Types 1) Fine Aggregate and 2) Coarse
Aggregate
Fine aggregate is the one that passes through 4.75 mm sieve and retained on 0.075 mm sieve
Coarse aggregate is the one that retains on 4.75 mm sieve.
Example of Fine aggregate – Sand
Example of Coarse aggregate – Gravel
Concrete :- Concrete is obtained by mixing cement, aggregate and water as per desired mix.
Here water to cement ratio plays important role. Strength of concrete is inversely proportional
to water cement ratio.
Concrete is represented by design mix as M-25.
M is Mix and 25 means compression strength at the end of 28 days considering concrete cubes
of 15 cm cube.
Concrete has Two setting types
a) Initial Setting time - 30 min
b) Final Setting time – 10 hrs
The test for setting time is done using Vicats apparatus.
Concrete setting time can be reduced or increased depending on climatic conditions by using
admixtures.
Admixture for increasing the setting time is called retarder and for reducing the setting time is
called accelerator.
