Experimental Field Investigation of the Effects of Lateral Load Distribution on Concrete Crosstie Track

Abstract

Increasing freight train axle loads and continued development of high speed rail has placed significant demands on North American rail infrastructure. To adequately address these demands, concrete crosstie and elastic fastening system design and performance must be improved. Field experimentation was conducted at the Transportation Technology Center (TTC) by researchers from the University of Illinois at Urbana-Champaign (UIUC) with the intent of proposing recommendations for improved concrete crosstie fastening system design and performance. The focus of this paper is on quantifying the distribution of lateral forces by use of the Lateral Load Evaluation Device (LLED) developed at UIUC to quantify the loading demands placed on fastening system components (e.g. insulators, clips, shoulders). Loading environment parameters (e.g. magnitudes, location, and train speed) were varied while recording lateral force and displacement measurements at critical interfaces. Other recorded measurements (e.g. vertical loads) are compared and discussed with the intent of investigating potential areas of track instability. Data will be used to improve the understanding of the lateral load path and the effects it has on demands placed on the fastening system. Ultimately, analysis of these data will influence future research on understanding the lateral load path and lead to improved mechanistic design practices for concrete crossties fastening systems.

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