Influence of Heavy and Long Train

Operation on Track Structure in the

Russian Railways Alexander Kosarev, Dr.Sc.in Engineering, Prof.

Deputy General Director

JSC “ Railway Research Institute” Moscow, Russia

General Characteristics of Russian Railways

• Operating length – 85200 km;

• Share of freight turnover in the Russian freight transport (with

pipelines) - 44.5%;

• Share of passenger turnover - 30.6%;

• Freight turnover - 2 196.2 bil.t, km. - coal 25%

- oil products 20%

- building materials 21% • Length of electrified lines - 43 300 km.;

• Length of CWR track - 67 000 km;

• Length of track on concrete sleepers - 70 000 km.

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Corridors of Heavy Haul Operations

Kuzbass

Nakhodka East Siberian-6300 km

Center - 3400 km

North-Weast -,4300 km

Murmansk

Moscow

South

5424 km

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RZD Strategy to Increase Train Weight

Stage 1. Increase in the train weight at the cost of more efficient utilization of

station tracks length (57 reference wagons) and traction means

improvement.

Stage 2. Increase in the train weight by increasing its length of up to 71

reference wagons.

Stage 3. Organization of heavy and long trains operation on the most

essential traffic-dense directions of the network.

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Accomplished Measures in Track

Stage 1 Stage 2 Stage 3

- removal of speed limits for freight trains depending

on track condition; - increase in the axle load of freight wagons of up to

22 t

- expansion of CWR with R 65 rails ; - application of increased quality rails ; - application of concrete sleepers with

increased shift resistance ; - application of elastic rail fastenings; - increase of cars axle load to 23,5 t;

-increase in the speed on the side track of railway turnouts up to 40 km/h

- increase in the axle load of wagons up 25 t;

- increase in the speed on the side track of turnouts up to

50km/h

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Solutions to Increase Train Weight

and their Consequences

Technical Solutions Increased action of forces Consequences

1. Increase in the train length without increasing the axle load/

load per meter of car length (linear load);

2. Increase in car axle load/linear load without increasing the number of axles in the train;

3. Integrated solutions, providing an increase in the number of axles along with simultaneous increase in the axle load /linear load.

Increase in impact of: – lateral and longitudinal loads on the track superstructure elements (for all variants); – vertical, lateral and longitudinal loads on track superstructure elements and vertical loads on track substructure (for variants with the increase in axle load/linear load.

- Increase in wear rate and faliure of track superstructure elements; - Increase in intensity of accumulation of track geometry disequilibrium and deformation of engineering structure elements and subgrade; - Increase in cost of repair and maintenance of track infrastructure objects.

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Main Results of Heavy Haul Traffic Studies

Conducted by JSC “VNIIZhT” in East

Siberian Region 1. Increase in the train length and weight without changing the axle load does not cause

significant changes in vertical impact on the track.

2. While putting the trains with increased weight into operation at sections with traction and breaking modes , there is an increase in tensile and compressive longitudinal forces in the train. This causes an increase in lateral and longitudinal forces applied to the track, especially in curves 400 m and less, on up and down grades more than 1.5%

Average values of lateral forces acting on rails under trains 5,000-6,000 tonnes do not exceed 100 kN, however maximum values of the these forces - 120kN ( train weight 6321 tonnes).

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Dependence of Horizontal Forces Acting

on Rail Head from Train Weight

Train weight, tonnes

Max

Average

Maximal and average horizontal forces in sharp curves (axle load -23.5 tonnes)

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Main Results of Heavy Train Operation

Studies conducted by VNIIZhT (cont.)

3. As additional measures to strengthen the track it was recommended to use КD-type fastenings, DN-6-65 type baseplates, seven-hole baseplates with high flange and laying of mixed track panel as a temporary measure. Both advantages and disadvantages of the mixed track panel were revealed in course of analysis of its behavior:

4. Costs for maintenance of track and permanent appliances increase depending on their share in the total train flow : - If the share of heavy haul trains with the increased weight and length does not exceed 10%, the rise of costs for the track maintenance amounts to ≈ 5 %, if 20% - to≈10% .

Advantages: Disadvantages:

- increase in the stability of the track gauge; - increase in the rigidity of the track;

- solution to the problem of spikes fracture; - increase in the gauge side of the rail head wear rate;

- increase in the life of wooden sleepers - partial deterioration of insert bolt holes in prestressed concrete sleepers after two years of operation.

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Bottlenecks that Impede the Regular Circulation of Trains with

Increased Weight and/or Length (cars of 25 t / linear load - 8.2 t )

- Track panel sections on wooden sleepers, especially in curves less than 650 m;

- Sections with the contradiction between the actual superelevation in curves and possible speeds of heavy trains (overload problems of the inner rail in curves);

- Sections with speed limit of up to 40 km/h on the side track through track switches (it makes more difficult to organize required 8-10 minutes interval between trains);

- Sections with unstable subgrade (about 3% of the total routes length);

- Engineering structures with insufficient load-carrying capacity and bridge approaches (necessity of arrangement of sections with variable rigidity).

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Measures Facilitating Decrease in the Impact on Track,

Intensity of Track Disorder and Maintenance Cost

- Driving trains with distributed traction;

- Implementation of electronic systems to control air-pressure braking along with the ensuring of synchronous braking of the whole train;

- Development of driving charts taking into account the actual track load-carrying capacity;

- Horizontal and vertical track alignment using coordinate technologies with the elimination of the track deterioration by using the “smoothing” method to improve dynamics of vehicle-track interaction.

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Studies for Further Development

of Heavy Train Operation - Finding actual track loading in the areas of heavy ( higher than 6,300 tonnes) and long train

operation;

- Development of methods to define actual track load-carrying capacity and standards of its allowable values, monitoring of the most loaded track sites in real-time mode;

- Definition of the track deterioration intensity increase depending on the share of heavy haul traffic;

- Development of track maintenance technologies to prevent defects due to the increased level of the track deterioration;

- Definition of rational spheres of reinforced track constructions application and methods of how to increase the load-carrying capacity of the railway subgrade elements and the engineering structures in conditions of the running of trains more than 6,300 tonnes;

- Optimization of modes of heavy haul trains driving taking into account actual load-carrying capacity and track loading, especially in sharp curves, while using temperature-stressed CWR track. 12

Thank you for your attention!