Abstract
This paper reviews the main failure modes of concrete ties observed in the U.S. railroads, including chemical degradation, prestress cracks, flexural cracks, rail seat deterioration, freeze-thaw cracks, and shoulder/fastener wear or fatigue. The observed characteristics, probable causes and detrimental effects of each failure mode are described. A finite element analysis framework aimed at achieving a better understanding of the basic failure mechanisms of concrete ties is presented. The ability of the modeling approach to simulate and predict critical failure modes of concrete ties is demonstrated. To meet the new challenges and demands placed on the U.S. rail infrastructure by increased high speed and heavy haul applications, concrete tie performance issues need to be addressed at both material and structural levels. Continued research needs to quantitatively characterize concrete tie failure under realistic track load and support conditions and to improve existing test and inspection standards are further discussed.