SLEEPERS IN CIVIL ENGINEERING

 

INTRODUCTION:

Sleepers are laid transverse to the rails on which the rails are supported and fixed. They transfer the loads from rails to the ballast and subgrade below.

FUNCTIONS OF SLEEPERS:

·         Holds the rails to maintain correct gauge.

·         Holds the rails in proper level or transverse tilt.

·         Distribute the load from the rails to ballast.

·         Provides longitudinal and lateral stability.

·         Provides means to rectify track geometry during service life.

REQUIREMENTS OF SLEEPERS:

v  It’s is Economical.

v  It’s Moderate weight.

 CLASSIFICATION OF SLEEPERS:

v  Wooden Sleepers

v  Metal Sleepers

ü  Cast Iron Sleepers

ü  Steel Sleepers    

v  Concrete Sleepers

ü  Reinforced concrete sleepers

ü  Prestressed concrete sleepers

                                         

WOODEN SLEEPERS:

v  It’s required for an ideal sleeper

v  The sleeper is depend upon their ability to resist the wear,decay,attack by vermin

v  The quality of timber is used in the sleeper

 

METAL SLEEPERS :

CAST IRON SLEEPERS:

In the cast iron sleepers there are five types:

·         Plot or bowl sleeper

·         Plate sleeper

·         Box sleeper

·         CST-9 Sleeper

·         Rail free duplex sleeper             

PLOT OR BOWL SLEEPER:

v  They consist of two bowls or plots and placed in the ballast

ü  The Bearing area is 0.232sq.m under each rail support

                    PLATE SLEEPER

ü  It’s consists of rectangular plates about 86.5cm side is parallel to the rails

ü  The position of plate is held in tie bars

                    BOX SLEEPER

Ø  Out of use these days

                    CST-9 SLEEPER

Ø  The weight of broad gauge tracks consists of 230kg

It’s is easily assembled and dismantled

v  SLATE SLEEPERS:

ü  These are inverted in channel folded ends

REQUIREMENTS:

·         Should maintain perfect gauge

·         Should have sufficient bearing area

SLEEPERS ADVANTAGES:

·         Easily available

·         In design the fitting are very simple

·         Economical.                                     

   SLEEPERS DISADVANTAGES:

ü  Alignment maintenance are very difficult

ü  Maintenance   cost is very high

ü  Track is easily disturbed        

v  DESIGN CONSIDERATIONS:

Material Selection: 

Sleepers should be in the environment and load condition

Spacing :

It’s is efficient and load distribution and stability

Size and shape :

Sleepers in the rail ballast depth

INNOVATIONS IN SLEEPERS:

v  Advanced materials:

Fiber reinforced polymers and recycled plastics

Improved designs:

Shapes are in better performance

         

v  POINT IN SLEEPERS ARE OFTEN USED IN:

1.  Rail track turnouts

2.    Crossings

3.    Junctions

4.    Bridge approaches                                                                                                                                

  CONCLUSION:

Ø Sleepers ensure the stability, safety and durability of infrastructure about proper design.

Ø Rail track stability and smoothness

Ø Load distribution and transfer

Ø Prevention of settlement and erosion

Ø Extension of infrastructure lifespan

    Sleepers are a fundamental component of civil engineering projects, requiring, careful consideration and ensure optimal performance and safety.

Author Bios:

Mr. D. Dhavashankaran, AP/Civil

Dr. N. Sridhar, AP/Civil

S. Sri Dhatchayini, III Year / Civil

S. Vinothini, III Year / Civil