Controlling Track Forces during Introduction of New High Speed Trains

Abstract
As part of its program to introduce a new generation of high speed trains in the United States, Amtrak, the owner of both the equipment and the infrastructure, defined an objective of minimizing any increase in track maintenance or damage to the track structure or its components. The concrete ties on the Northeast Corridor were a particular source of concern in light of the tie cracking problems that had been experienced by Amtrak in the 1980s. The primary focus of attention was the dynamic wheel/rail impact forces applied to the track structure. Research studies have shown that significant increases in wheel/rail dynamic forces can occur at high speeds with a corresponding potential increase in track degradation, component failure, and track maintenance costs. To avoid this effect, Amtrak introduced a specific requirement for the design of the new high speed Northeast Corridor equipment to maintain the level of dynamic vertical wheel/rail forces applied to the track no higher than current levels. Thus for proposed new electric equipment to be operated at 150 mph, the dynamic impact forces were set at a level corresponding to the existing AEM7 electric locomotive operating at 125 mph. Likewise for the proposed new fossil fuel (diesel) equipment to be operated at 125 mph, the force levels were set to that of the existing F40 diesel locomotive operating at 90 mph.
Description
Keywords
Rail dynamics, Track degradation
Citation
Zarembski, A.M., Palese, J.W., Bell, J.G., “Controlling Track Forces during Introduction of New High Speed Trains”, International Railway Journal, October 2001