FATIGUE DAMAGE EVALUATION METHOD, FATIGUE DAMAGE EVALUATION SYSTEM AND FATIGUE DAMAGE EVALUATION DEVICE

PROBLEM TO BE SOLVED: To enhance the accuracy of a life evaluation by improving the accuracy of a fatigue damage rate in an initial stage of life.SOLUTION: In a method for evaluating the life of a structure by regarding damage of a structure based on fatigue damage or creep fatigue damage as progress of a minute crack and predicting progress of the minute crack, a fatigue damage evaluation method uses master curve calculated by a relation of log( a)=A* f+B(A, B: constant) in the case that the total sum of minute crack lengths is a, and the fatigue damage rate is f, wherein the total sum a of the minute crack lengths is acquired from the total sum of two or more minute crack lengths including the longest minute crack length. 【課題】寿命の初期段階における疲労損傷率の精度を向上させ、寿命評価の精度を高くすること。【解決手段】疲労損傷あるいはクリープ疲労損傷に基づく構造物の損傷を微小き裂の進展とみなして、該微小き裂の進展を予測することにより前記構造物の寿命を評価する方法において、微小き裂長さの総和を a、疲労損傷率を ｆとした場合、log( a)＝Ａ・ ｆ＋Ｂ（Ａ,Ｂ：定数）の関係で求められるマスターカーブを用い、前記微小き裂長さの総和 aは、最大長さの微小き裂を含んだ２本以上の微小き裂長さの総和から求めることを特徴とする疲労損傷評価方法。【選択図】図１