冻融环境下混凝土力学性能试验及损伤演化

在我国西部寒区，冻融作用往往是导致混凝土破坏的主要因素之一。通过对饱水状态下的多组混凝土试样进行冻融循环试验，并对试验后的试样进行了单轴压缩试验，从损伤和能量耗散的角度对试样进行了力学性能的分析；运用CT细观试验的方法初步对经历不同冻融循环次数下的试样进行了细观结构分析。通过试验研究，得到了饱水状态下混凝土材料的冻融破坏特征，以及不同冻融循环次数下试样质量、单轴应力-应变全过程曲线、抗压强度、能量耗散和细观结构的变化特征，系统研究了冻融循环下混凝土主要物理力学性能及损伤演化规律，为寒区重大工程冻融灾变预测提供较可靠的基础依据。

Experimental study on the mechanical property and damage evolution of concrete under freeze-thaw environment

In cold regions of west China,freeze-thaw environment is one of the main factors for leading to the damage of concrete.The freeze-thaw cycling experiment was conducted on concrete under water-saturated conditions,the uniaxial compression experiments were carried out on different freeze-thaw cycles,and the mechanical properties of concrete specimen was systematically analyzed from the perspective of damage and energy dissipation.After freeze-thaw test,the meso-structures of the concrete specimens were preliminary researched by CT meso-test method. Then the failure forms of the specimens under water-saturated and the changes of the mass, the complete stress-strain curves,uniaxial compressive strengths,energy dissipation and the variation characteristics of meso-structures of the concrete specimens after different freeze-thaw cycles were obtained.The main physic-mechanical properties and fracture law of concrete weres explained under freeze-thaw environment. The results can provide the theory basis for major engineering freeze-thaw catastrophe prediction and prevention research in the cold region.