Springfield Express, Math Problem Example

During the past few decades, there has been a renewed interest in the amplification of the passenger railroad serviced in various parts of the United States. This renewed interest has included passenger transport services between urban areas and particularly, the urban commuter train service which takes place in the more expansive municipalities. There have been a number of factors which have come to pass in order to stimulate the renewed interest in passenger rail service. Some of these factors are the requisites of diminishing the congestion which is taking place in the other modes of transport (i.e., highway and airport traffic) and to diminish the elevated indexes of air pollution. The attractive aspects of the passenger rail systems are the capacity of making available function of the rights of way which are possessed by the railroad system and the capacity of mass public transport at comparatively low rates (Solomon 170).

An outcome of this renewed interest is a significant and increasing investment in the new railroad system passenger transport cars for the application in the United States. Approximately 200 newly constructed railroad cars are put into service annually. In endeavors to enhance the production and the passenger comfort on the railroad passenger cars, some of the designs will incorporate features which have not been previously considered in then Untied States railroad system.  Previously, there have b been issues with the implementations of novel features which were incorporated into the new railroad car service. This might include the application of track modifications or operational modifications in order to assure that the passengers receive a smoother ride (U.S. Department of Transportation 2-12).

Engineering review is required in order to resolve issues of passenger comfort. Operational track issues may be addressed as the newly constructed passenger railroad cars may encounter issues which had not been considered in previous designs.  The optimal designs for the new passenger railroad cars must include the following safety considerations in order to minimize risk and to increase the passenger comfort level.  The newly constructed railroad cars must have the capacity of being supported by the rail by applying sufficient load paths from the railroad car body to the tracks in the circumstances of longitudinal, vertical and lateral loads. The load directions of guidance, braking, acceleration and gravitational forces are applied to the railroad cars and subsequently to the railroad passengers (U.S. Department of Transportation 2-13).

The railroad vehicle must possess the capacity of being guided along the railroad track in the absence of rail or wheel forces which could cause the risk of unanticipated track damage or railroad car derailments. This requisite infers the avoidance of the aspects of dynamic instability and the production of excessive forces during the incursion of curves. The railroad cars must be able to isolate the passengers for the irregular aspects of the railroad track in order to provide the railroad passengers with a comfortable railroad experience.  The railroad cars must perform these functions while accommodating a number of diverse auxiliary components which include gearboxes, electrical motors and braking systems (U.S. Department of Transportation 2-13).

The diverse variety of railroad track designs has been modified. Extensive reconstruction in decade long cycles is required for the passenger railroad cars. The cost value of the locomotives which are two, three, four and five decades in age are able to transport passengers in a more cost avoidant manner than when they had been procured as new equipment. Many of the railroad systems apply locomotives and passenger cars which have been reconstructed in lieu of adding completely new equipment. The rebuilt units have a cost aspect which is twenty five percent of the new units. The locomotives and the passenger cars have the tendency of being constructed from stainless steel material. This aspect guarantees a long life span and extensive service. The only time that the passenger railroad cars cannot be reused or rebuilt is when corrosion has invaded into the load bearing positions (Solomon 171).

Research has demonstrated that for distances which are inferior to three hundred miles, the application of high speed trains has the capacity of competing with air travel as a viable means of passenger transportation. This is the causal attribute between the production of high speed trains in Europe and Asia. The cities which have populations of 150,000 or more are less than one hundred and fifty miles in separation in Europe and Japan. This is the aspect which has caused the development of the high speed rail transport to lag behind the European and Japanese productions. The exception to this aspect is the densely populated corridor which is existent on the Northeastern Atlantic seaboard from Washington DC to Boston MA  (U.S. Department of Transportation 2-13).

The production of elevated velocity trains provided encouragement of the technological innovations which pertain to their aspect of velocity. The comprehensive electrification of the high speed trains become conventional and the application of the diesel electric trains became commonplace. Magnetic levitation railroad systems have shown the capacity of being able to operate at velocities upwards of three hundred miles per hour (U.S. Department of Transportation 2-13).

The railroad tracks of the railway system must be designed with gradual changes in horizontal alignment. The tracks need more horizontal clearance than other types of public transportation (i.e. passenger vehicle roadways). The more expansive horizontal clearance is correlated with the requisite of designing larger train cars. The normal railroad car is about eighty five feet long (U.S. Department of Transportation 2-13).

The resistance of the railroad curves augments in correlation with the extent of the curve. It has been assessed that a curve which has a twelve degree inclination augments the resistance which experienced by the railroad cars in motion by 100% in comparison to the forces which are experienced by the railroad car on a segment of railroad track which is level. . The rack segments which must overcome steep gradients have shown that it might be required to diminish the grade of the elevation in order to provide equilibrium for the aspect of curvature.  An inclination with a grade of one percent provides a railroad car resistance of twenty pounds for each ton. Diminishing the inclination by 1/ 25 of a degree will balance the railcar resistance which experience by a one degree horizontal curve.  The greatest allowable context of the curvature is varied with the characteristics of the terrain which must be traversed by the railroad cars and locomotive (U.S. Department of Transportation 2-13).

The dimension of the vehicles influences the behavior and the ride which is experienced by the railroad passengers. The application of longer railroad cars requires a more expansive minimal radius of curvature. . The optimal minimal radius for the mainline railroad tracks is approximately 1/ 5 mile. In the railroad maintenance yards curves which are up to forty degrees in inclination can be found.  In the circumstance of the railroad superior elevation, the railroad car which is experiencing a curve is influenced by a variety of forces. The forces which are experienced by the railroad car is the resisting force which is experienced by the railroad cars as it travels on the rails, mass and centripetal forces (U.S. Department of Transportation 2-13).

In order to compensate for these forces and to provide the railroad passengers with a smoother, more stable ride, it is required to provide a superior elevation to the roadways or the railways which enable the railcar to safely experience a curve without having the risk of slipping at the design velocity. In many engineering manuals this aspect is referenced as SE. A SE which is equivalent to 10% would be representative of a slope which is equal to 0.10 feet decline per foot which is traveled. At increased velocities, the centrifugal force which is experienced causes the railcar passengers to experience discomfort as the outer train rail is subjected to lateral pressures. The aspect of superior elevation of the railroad tracks will compensate for both tendencies (U.S. Department of Transportation 2-13).

Consequently, in order to provide a safer and smoother ride for the railroad passengers, the United States’ restriction to superior elevation is eight inches.  These indexes are reliant on the extent and the radial aspect of the curves. In the railway characteristic of superior elevation, the optimal resistance for the railroad cars is zero at the designed velocities. The aspect of the ideal friction being valued at zero causes the railroad car wheels to adhere more effectively to the interior of the railroad tracks.  The risk which occurs over a period of service is that the lateral centripetal forces cause the railroad track to go out of the optimal alignment range (Solomon 172).

The aspect of applying baking to a curve is fulfilled by raising the outside rail. In order to provide a smoother ride for the passengers on the way to curves which have a superior elevated aspect, the superior elevation is usually incrementally increased by the index of one inch per half foot on the tangent which defines the approach and diminished by the identical context after concluding the curve. Each of the designed railroad curves should be considered for comfortable banking at the velocities which are designed (U.S. Department of Transportation 2-13).

Works Cited

Solomon, Brian. Intermodal Railroading. St. Paul, MN: Voyageur Press, 2007. Print.

U.S. Department of Transportation. “Design data on suspension systems of rail cars.” National Technical Information Service, 1996. Print