Li Wenhao, Hu Shaowei
School of Civil Engineering, Chongqing University, Chongqing 400045, China.
Yellow River Laboratory, Zhengzhou University, Zhengzhou 450001, China.
Materials (Basel). 2023 Sep 14;16(18):6205. doi: 10.3390/ma16186205.
Fracture behavior is one of the key properties to study concrete cracking under sodium chloride attack exposed to the freeze-thaw cycles environment, which is frequently neglected. In this paper, 24 single edge notch beam specimens and 24 cubes were poured. The corresponding freeze-thaw cycles test in sodium chloride solution, standard cube compressive strength of concrete test, and three-point-bending tests were carried out. The research revealed that the fracture toughness, fracture energy, relative dynamic modulus of elasticity, and standard cube compressive strength were decreased by increasing freeze-thaw cycles under sodium chloride attack, and the damage degree of concrete caused by sodium chloride solution was deeper than that of pure water. In particular, there existed good linear correlation between the fracture behavior and imposed freeze-thaw damage for various solution. Accordingly, a more reliable damage model using fracture control parameters as damage factors was proposed.
断裂行为是研究处于冻融循环环境下遭受氯化钠侵蚀的混凝土开裂的关键性能之一，而这一性能常被忽视。本文浇筑了24个单边切口梁试件和24个立方体试件。进行了相应的在氯化钠溶液中的冻融循环试验、混凝土标准立方体抗压强度试验以及三点弯曲试验。研究表明，在氯化钠侵蚀下，随着冻融循环次数的增加，断裂韧性、断裂能、相对动弹性模量和标准立方体抗压强度均降低，且氯化钠溶液对混凝土造成的损伤程度比纯水更深。特别是，各种溶液作用下的断裂行为与冻融损伤之间存在良好的线性相关性。据此，提出了一种以断裂控制参数作为损伤因子的更可靠的损伤模型。
