Study on fatigue life of ballastless track fastener springs based on a fatigue test

Abstract

Purpose Fastener technology is one of the key technologies of the ballastless track structure, and the spring strip is the key component to realize the fastener function. Based on the fatigue test of the WJ-7 type fastener of the ballastless track in China, it is concluded that the fatigue damage of an elastic strip is the main reason for the decline of service performance of the fastener. The purpose of this paper is to discuss the fatigue life of the fastener. Design/methodology/approach First, a DH3818 static strain tester is used to measure the static strain signal in the elastic strip fatigue test, and then the fatigue limit of the WJ-7 elastic strip is calculated. Finally, the fatigue life of the fastener strip is estimated. Findings The findings of the paper are as follows: first, the lowest fatigue life with a survival rate of 99 percent should be taken as a reference for the service times of WJ-7; second, the fatigue life of the modified formula found to be short under the same stress amplitude. Originality/value The fatigue test is processed by the authors and the results of elastic strip are obtained based on the test. Meanwhile, the corresponding limit value of the fatigue stress amplitude is calculated based on the tested results.