Prestressed Concrete Sleepers Importance and Innovation

Prestressed Concrete Sleepers Importance and Innovation

Gauthaman P Assistant Professor

Civil Engineering, Prist University Puducherry, India

AbstractIn this paper, Prestressed Concrete Sleepers are discussed briefly and observed various parameters governing the same. It is advantageous in rapid making of the material and in terms of high strength requirements.

KeywordsPrestressed Concrete Sleepers; Finite Element Modeling

TABLE I. DESIGN PARAMETERS

1. INTRODUCTION

   Prestressed Concrete Sleepers are designed to resist dynamic form of loading mainly. Freyssinet developed a sleeper with 2mm diameter wires, wound continuously as a thread, and pretensioned by rods passing through the loops at each end. The principle function of the sleepers is to distribute the wheel loads carried by the rails to the ballast. Factors affecting the design of sleepers are a) the static and dynamic loads imposed on rail seats b) the ballast reaction on the sleeper1.

2. METHODS OF APPLICATION-PRESTRESSING METHODS

   The prestressing wire shall be stretched either individually or collectively by an approved method. However, the stretching force shall in no case exceed 75 % of the minimum specified UTS of the wire. The pre-tensioning force in the wire shall be applied by a tensioning device equipped with automatic load cut off unit along with measuring gauge2.

3. DESIGN ASPECTS

From the consideration of Indian Hume pipe co.ltd. Which is manufacturing company of railway sleepers (prestressed concrete sleepers), the same is advantageous over a) timber sleepers b) post-tensioned monolithic type c) two block sleepers. So nowadays, monolithic type model is being used for Railway Sleepers. The following Table1 depicts different parameters for different set of countries and comparison is made.

IV ANALYSIS AND DESIGN

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For the prestressed concrete analysis, ANSYS software provides a state of art solutions to analyze the structure. Procedure will be discussed briefly. Boundary Conditions would be set initially, meshes are developed and load should be applied and the bending stressed could be observed using analysis. This comes under finite element analysis of the concrete beam.

Fig1. Finite Element Modeling V CONCLUSIONS

It is thereby understood that prestressed concrete sleepers are good in design and execution. So overall, it has to be optimized for better results in terms of economy and safety considerations. In future, research could be given priority for such prestressed concrete sleepers, so it could be used effectively under practical conditions.

REFERENCES

1. Fundamentals of Prestressed Concrete, Textbook, S.K.Roy

2. Standard Specification for Pre-tensioned prestressed concrete sleepers for Broad Gauge and Metre Gauge, Fourth Revision May2011

3. Prestressed Concrete Book by Krishna Raju, Fifth Edition.

4. Indianhumepipe.com/Products/ConcreteSleepers.aspx.

5. Nonlinear finite element modeling of railway prestressed concrete sleeper, Sakdirat Kaewunruen, University of Wollongong, 2006