冻损梯度对承压混凝土应力-应变关系的影响

Effect of Frozen Damage Gradient on Stress-Strain Relationship of Stressed Concrete

对不同冻融损伤程度的混凝土圆环体试件进行了试验研究.结果表明:当相对冻融深度小于临界值时,混凝土的峰值应力、峰值应变均呈线性退化,超过临界值后则保持稳定;当冻融循环次数由100次增加到200次时,相对冻融深度临界值由0.5增大到0.8;基于应变等价性假说和统计损伤理论,建立了不同冻融损伤程度下承压混凝土的应力-应变关系模型.

Experimental research was conducted on concrete torus‑shaped specimens with different degrees of freeze‑thaw damage.The results show that when the relative freeze‑thaw depth is less than the threshold,the peak stress and peak strain of concrete exhibit linear degradation,while remained stable after exceeding the threshold.When the number of freeze‑thaw cycle increases from 100 times to 200 times,the threshold of relative freeze‑thaw depth increases from 0.5 to 0.8.Finally,based on the hypothesis of strain equivalence and statistical damage theory,the stress‑strain relationship model of stressed concrete with different degrees of freeze‑thaw damage is established.