现有钢筋砼结构耐久性评定标准

The durability of concrete structures has caused much attention of engineering. The major causes which may attack structural integrity gradually are such as corrosion of reinforcement, freezing and thawing cycle, alkali-aggregate reaction and other biologic and chemical erosion ea al.. The researches on the durability of concrete structures are carried in view of material science while in other view of structural engineering. In view of building material science, the main purpose is to reveal the degradation mechanism of the nature of the material varying with time, in view of structural engineering; it is to reveal the influence of the degradation of nature of reinforced concrete on the capacity of structures such as the reliability, serviceability and safety of structures. To a certain extent, the two points of view of the structural durability research are identical. But almost all the research works are the determinate individual factor analysis instead of the indeterminate multi-factor coupling mechanism analysis. In facts, the structure is always under the coupling effect of multi-factor such as corrosion of reinforcement, freezing and thawing cycle, alkali-aggregate reaction, while accompanied by the action of external load. Compared to the research efforts to the durability of structural components, those to structural system are insufficiency, although they are important to the prediction of the survival lifetime of on-serving structures. To render the durability theory to the practical engineering, there is also some research needed to undertake.For the reasons mentioned above, base on the theory of building material degradation mechanism in the serving condition of common atmospheric, and summary of research on the effect of reinforced concrete deterioration on structural durability, the durability appraisal criteria of existing reinforced concrete structures which under the action of multi-factor is present. The Markov process model is raised to characterize the time-varying of the corrosion of reinforcement in concrete, which modeled the continuity, un-reversible, and non-memory on the process of the corrosion of reinforcement. One neural-net-work model to analysis the durability of structural system is proposed, and the expert system for the durability assessment of in-serving reinforced concrete structures is also present with the rationality and practicality of the model being tested by a practical project.

揭示钢筋西欧、西欧锈蚀、冻融循环等多因素耦合作用下结构构件抗力变化的规律；研究满足正确工程决策需要的钢筋砼结构系统失效概率范围的确定和计算；现有钢筋砼结构耐久性评定标准的设置；现有钢筋砼结构剩余寿命的预测，为现有钢筋砼结构的耐久性设计、耐久性评估、剩余寿命预测以及建筑物鉴定工作的规范化打下基础。.