Chang Hoon Lee, Ph.D.
Assistant Professor, College of Engineering
Western New England University
Engineered Cementitious Materials for Durable Railroad Crossties
Prestressed concrete crossties have become a critical structural component of safer and durable track structures. Currently, the structural performance of prestressed concrete crossties varies widely due to several design parameters including material properties, cross-sectional dimensions, and types of prestressing tendons. As more options of the compositions in the fabrication of cement-based materials have been available, “tailor-made” cement-based materials aiming at specific performances of the application have been highlighted. A popular example is the so-called “Ultra-High-Performance Concrete (UHPC),” which has been used for limited applications necessary for achieving smaller member dimensions, higher performance to complex loading conditions, long-lasting durability, and aesthetics. However, the current use of UHPC is mostly prescriptive in terms of performance, demanding rigorous evaluation of the necessity of its use. Also, application of UHPC to the mass production of crossties is questionable in terms of cost-benefits. Furthermore, its quality and price is dependent on the locally available materials. This research focuses on the development of an engineered cementitious material (ECM) for producing high performance when serving as prestressed concrete crossties. As initiated by identifying the required performances as the railroad crossties, the mixture proportion is developed for ensuring structural performance, durability, finishing condition, and cost-effectiveness. Accordingly, this research presents the principles of the mixture design, structural, and durability performances, which can provide the guideline of its application to prestressed concrete crossties.