W1 type fastener spring bars are one of the commonly used spring bars in ballastless tracks of high-speed railways. High-speed railway spring bars are subjected to repeated and variable loads during actual work, and the strength of the spring bars will gradually change and fatigue failure will occur. This article takes W1 spring bar as a column. First, the raw material 60Si2MnA spring steel of W1 spring bar is processed into test specimens for static tensile test, and the yield strength of spring steel is 1600MPa and the tensile strength is 1900MPa; Then, the W1 elastic bar is subjected to a strain electrical test to measure the stress changes of each part of the elastic bar, and the position where the stress value of the inner arc of the elastic bar is the largest and the most easily broken is obtained, and 25KN is the best installation preload of the elastic bar; Three different cyclic loading conditions are applied to the W1 spring bar by the MTS810 servo hydraulic testing machine, and the change law of the spring bar"s buckle pressure and the arc displacement of the middle ring under the cyclic load is studied. The test shows that the change with the fatigue load The number of cycles increases. The spring bar buckle pressure and the arc displacement of the center circle are in antiphase relationship. The fatigue life of the spring bar under 5KN, 7.5KN, and 10KN cyclic loads are 820,000 times, 190,000 times, and 70,000 times respectively. The relationship between the arc displacement of the middle circle of the spring bar and the buckle force is fitted by the test data.