Durability Design and Conservation for Concrete Structures in Cold Region Subjected to Combined Deterioration Effects

在寒冷地区的混凝土结构中，混凝土中的水在冻融循环中发生冻害。提出了一种利用超声波测量实际结构冻损程度的方法。观察了冻害程度与材料性能退化之间的关系。阐明了冻害和干湿循环/盐侵蚀共同作用下的劣化机理，提出了模拟劣化的模型。提出了覆层修复后结构冻损的数值分析模型。

In concrete structures in cold regions frost damage is occurred by freeze-thaw cycles of water in the concrete. This study presents the method to measure the degree of frost damage in actual structures using ultrasonic wave. The relationship between the frost damage degree and degraded material properties is observed. The deterioration mechanism under the combined effects of frost damage and wet-dry cycles/salt attack is clarified, and then the models to simulate the deterioration is proposed. The model for numerical analysis of structures with frost damage after being repaired by overlaying is also proposed.