论文部分内容阅读
分析了混凝土压缩疲劳寿命的主要影响因素,认为静载下的韧度可以衡量其疲劳寿命;确定了适合的韧度表示方法,建立了混凝土材料静力韧度指标和疲劳韧性之间的关系表达式,从而以静力韧度的测量来代替疲劳韧性,可以大大减少工作量。建立了材料疲劳韧性随疲劳次数耗散模型的数学表达式。在试验基础上,以疲劳韧性消耗作为损伤变量,推导出以静载韧度表达的混凝土疲劳损伤演化方程,发现损伤发展率呈三阶段规律。经对比验证,在不同应力水平下,以静载韧度表示的损伤演化规律与用疲劳韧性表达的损伤规律吻合较好。
The main influencing factors of compressive fatigue life of concrete are analyzed. It is considered that the toughness under static load can measure its fatigue life, and the suitable method of toughness is established. The expression of the relationship between static toughness and fatigue toughness of concrete is established Style, so as to measure the static toughness to replace the fatigue toughness, can greatly reduce the workload. A mathematic expression of the material fatigue toughness with fatigue dissipation model was established. On the basis of the experiment, fatigue damage was taken as the damage variable, and the fatigue damage evolution equation of the concrete, which is expressed by static load toughness, was deduced. It was found that the damage development rate showed a three-stage law. After comparison and verification, under different stress levels, the damage evolution law indicated by static load toughness is in good agreement with the damage law expressed by fatigue toughness.