Measurements of rail-to-tie deflections and fastener slip strain were made on both concrete and wood tie track at the Facility for Accelerated Service Testing (FAST) in October 1980. These measurements were made to provide a data base for duplicating, if possible, these deflections and strains in a laboratory. The laboratory tests would serve as the basis for evaluating the performance of various wood and concrete tie fasteners.
The results demonstrated that rail-to-tie deflections are a reasonable way to characterize the fastening load environment. However, because of the complexity of fastener deflection, better results would have been obtained by direct measurement. The rail-to-tie deflections measurement did provide enough data to develop appropriate laboratory fastener performance tests.