North American railways have experienced significant traffic growth over the past 20 years to the point where many lines are at or near capacity. While the current worldwide recession has eased capacity constraints momentarily, the long-term trends are for continued traffic growth. Faced with the prospects of perhaps doubling freight traffic demand in the next 20 years and adding significant passenger traffic, the railroads are developing cost effective ways to increase capacity. Besides constructing additional tracks, improving the performance (i.e., safety, reliability, and service lives) of key track components is expected.Both heavy axle loads (HAL) and high speed rail (HSR) passenger traffic require high quality, durable track. The paper will describe recent work done to improve the dynamic performance and durability of these track components:• Special trackwork• Rail joints• Crossties• Track transitionsFor example, turnouts are being developed that can accommodate freight shippers served from mainline track that also carry high speed traffic. These continuous mainline rail switches and frogs allow slow speeddiverging operations that will not affect mainline track performance.The paper will also discuss further heavy haul infrastructure research and development needs.
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