The Federal Railroad Administration (FRA) contracted with Transportation Technology Center, Inc. (TTCI) to investigate the spike loading environment in various wood-tie fastening systems. The goal was to understand how dynamic loads are transferred to the spikes in wood-tie fastening systems and identify feasible solutions to the spike breakage issue. Field testing was conducted on a six-degree curve at FRA’s Transportation Technology Center (TTC) in Pueblo, CO, in 2021. Researchers instrumented four common wood-tie fastening systems with strain-gaged cut spikes to determine their real-time dynamic bending strains.