The fatigue life range for the suspenders of suspender supported arch bridges is from 3 to 16 years. So the suspernders will break and be repaired possibly many times during the whole service life of the bridge. The estimated fatigue life of the suspenders is not a definite value since the estimation is based on statistical analysis. That means that the moment when the suspender breaks can only be located in a range instead of an exact date. During the estimated possible fatigue life range, the suspenders and the bridge may break abruptly at any moment. That is to say, the bridge may be destroyed unexpectedly due to the undetermined fatigue failure of the suspenders.Based on the failure safety theory, the study on the failure safety suspender systems of the suspender supported arch bridges is carried out. This avoids the uncertainty of the statistical fatigue life estimation. The failure safety suspender systems make it possible that the bridge will not collapse abruptly and unexpectedly due to the failure of some suspenders of that bridge. And the repairment of the damaged or broken suspenders can be realized right after the suspender failure happens without the whole bridge being closed for traffic.
