Concrete structures suffer some damage yet not failed under fatigue load, and then continue to bear 3D redistributed stress. For this, the 3D fatigue loading considering various fatigue factors (e.g. confining stress, axial static stress (ASS) and force amplitude (FA), frequency, and cycle number) is first carried out, and then the 3D static loading is performed. The post-fatigue characteristics of high-strength concrete (e.g. P-wave velocity, S-wave velocity, porosity, gas permeability, triaxial compression strength, and elastic modulus) are gained. The results indicate that 3D fatigue loading weakens mechanical properties, delays wave propagation, and increases seepage paths. An obvious stress threshold is exhibited with increasing axial static stress and force amplitude, that is 80% triaxial compressive strength, where the physico-mechanical characteristics are rapidly weakened due to the energy dissipation caused by crack growth rises increasingly. Compared with 1D fatigue loading, the frequency turning point of weakening effect from decreasing to increasing is advanced under 3D fatigue loading due to the application of 3D stress exacerbates the heat accumulation and creep damage generation. Interestingly, the fatigue damage is likely to be more sensitive to axial load compared to confining stress during 3D fatigue loading. In other words, the promotion effect of axial fatigue load on damage is larger than the restriction of confining stress. Furthermore, the fatigue damage models considering various fatigue factors are proposed. Then, the empirical prediction models of this damage variable to mechanical parameters (strength and elastic modulus) and permeability are established to predict the capacity loss caused by fatigue loading in the design of concrete construction. The testing results in this context could facilitate our understanding of post-fatigue characteristics of high-strength concrete subjected to 3D fatigue loading and guide the safe design of concrete construction.

混凝土结构在疲劳荷载作用下受到一定程度的破坏但并未失效，然后继续承受 3D 重新分布的应力。为此，首先进行考虑各种疲劳因素（例如围压、轴向静应力（ASS）和力幅（FA）、频率和循环次数）的 3D 疲劳加载，然后进行 3D 静加载。获得了高强度混凝土的疲劳后特性（如纵波速度、横波速度、孔隙率、透气性、三轴抗压强度和弹性模量）。结果表明，3D 疲劳载荷削弱了机械性能，延迟了波的传播，并增加了渗流路径。随着轴向静应力和力幅值的增加，表现出明显的应力阈值，即80%的三轴抗压强度，由于裂纹扩展引起的能量耗散增加，物理力学特性迅速减弱。与一维疲劳加载相比，由于3维应力的施加加剧了热积累和蠕变损伤的产生，在3维疲劳加载下，减弱效应的频率转折点提前了。有趣的是，与 3D 疲劳载荷期间的围压应力相比，疲劳损伤可能对轴向载荷更敏感。换言之，轴向疲劳载荷对损伤的促进作用大于围压的限制。此外，提出了考虑各种疲劳因素的疲​​劳损伤模型。然后，建立了该损伤变量对力学参数（强度和弹性模量）和渗透性的经验预测模型，以预测混凝土结构设计中疲劳载荷引起的容量损失。在此背景下的测试结果有助于我们了解承受 3D 疲劳载荷的高强度混凝土的疲劳后特性，并指导混凝土施工的安全设计。