盐侵蚀与冻融循环耦合作用下活性粉末混凝土的耐久性及其破坏机理研究

项目名称： 盐侵蚀与冻融循环耦合作用下活性粉末混凝土的耐久性及其破坏机理研究

项目编号： No.51278039

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 建筑科学

项目作者： 安明喆

作者单位： 北京交通大学

项目金额： 83万元

中文摘要： 寒冷地区海洋环境、盐碱环境及除冰盐环境下，钢筋混凝土结构的服役条件极其恶劣，在多环境因素耦合作用下破坏十分严重。为此，这些结构物的防护问题已成为亟待解决的科学问题。活性粉末混凝土作为新型复合材料，具有高耐久性、超高强度、高韧性及高体积稳定性等特点，特别适合用做上述服役环境下的主体结构材料与防护材料。本项目通过氯盐侵蚀与冻融循环、硫酸盐干湿交替与冻融循环耦合作用试验，确定活性粉末混凝土物理力学性能指标的变化规律，提出配合比参数、养护温度和耦合机制对耐久性的影响规律，给出性能指标演化方程，提出耐久性评价指标与方法；结合微观分析试验与理论分析，阐述耐久性能衰退与破坏机理；结合复合材料损伤疲劳理论，构建基于耐久性评价指标的多参数损伤度表达式，给出耐久性失效判据,建立复杂服役环境下的活性粉末混凝土寿命预测模型。本项目为复杂服役环境下，采用活性粉末混凝土进行结构设计和防护设计提供理论基础。

中文关键词： 活性粉末混凝土；耐久性；盐侵蚀；冻融循环；耦合作用

英文摘要： Reinforced concrete structures in harsh service environments like cold regions, marine environment, saline environment, deicing salt environment are badly damaged under the coupled various factors. Therefore, efficient structure protection has become a scientific problem must to be solved. Reactive Powder Concrete is a cement-based composite material, which possesses high durability, high strength, high toughness and high temperature adaptability etc. And it is suitable for the main structural material and protective material in the harsh service environments. In this project, the coupling of chloride and freeze-thaw cycles test, and the coupling of sulfate dry-wet cycles and freeze-thaw cycles test are carried to ascertain the physical and mechanical performance index of Reactive Powder Concrete. The influence of mix proportion parameters and curing temperature and coupling effect to the durability are studied, while the physical and mechanical performance of evolution equation are provided. Then the durability evaluation index and methods are suggested. Furthermore, elaborate the mechanism of recession and damage through the microcosmic-test combined with theory analysis. Build the multiparameter damage degree on the basis of the durability evaluation index according to damage fatigue theory of composite mater

英文关键词： Reactive powder concrete；Durability；Salt erosion；Freeze–thaw cycle；Coupling action