Uniaxial compression test was carried out on standard cube specimens under different strain rates (10-5, 10-4, 10-3, 10-2/s), and damage variable was defined with concrete elastic modulus as the parameter.Damage evolution rules and variation of critical point of damage with strain rate were analyzed under stress space.Results show that with the increase of strain rate, 1) the stress level at critical point of damage rises, and the first and second critical points move to the positions of higher stress level;2) the interval length of first phase of damage increases and the interval length of third phase reduces, but the change of strain rate has little effect on the interval length of the second phase, which remains about 0.3.%为对混凝土损伤阶段进行划分,并确定损伤界点,对标准立方体试件进行了不同应变速率(10-5,10-4,10-3,10-2/s)下的单轴压缩试验,定义以混凝土弹性模量为参量的损伤变量,并在应力空间下对混凝土损伤演化规律及损伤界点随应变速率的变化规律进行了深入分析.研究结果表明:①损伤界点应力水平随着应变速率的提高而上升,应变速率的提高使得损伤第1界点与第2界点向着应力较高处推移;②随应变速率的提高,损伤第1阶段区间长度增加,第3阶段区间长度减小,但应变速率的变化对损伤第2阶段影响甚微,且第2阶段应力区间长度在0.3左右.
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