Performance Verification and Judgment on Existing Concrete Structures Based on Reliability Basis

(1)养护是保证混凝土结构使用性能的重要环节。提出了通过将设计、施工与维护相结合并同步来保证在所要求的服务期内保持所需性能的概念。在这种情况下，指出了设定可靠度限值的重要性。(2)为了通过极化电阻监测钢筋混凝土梁的腐蚀情况，评估钢筋混凝土梁的劣化程度和性能，对钢筋混凝土梁进行了盐水条件下的试验研究。对锈蚀前后的构件进行加载试验，测量锈蚀钢筋的重量。(3)在反复反复荷载作用下，ASR锈蚀混凝土构件的承载能力仍存在许多不确定点。在此基础上，对ASR劣化的钢筋混凝土梁进行了反复荷载试验。(4)评估混凝土强度的分散和分布对在役混凝土结构可靠性分析的重要意义。本文对考虑混凝土强度分布的钢筋混凝土梁进行了荷载试验。参照氯离子劣化机理研究结果，对氯离子劣化钢筋混凝土桥梁部分参数的不确定性进行了研究，并对结构进行了性能评估。此外，由于钢筋锈蚀和循环荷载的作用，由多根主梁组成的桥梁结构存在主梁刚度退化的问题。在考虑梁刚度退化引起的截面内力分散的情况下，对这种桥梁进行了安全性评估。

(1) The maintenance plays an important role for the performance guarantee of a concrete structure. The concept of guaranteeing to maintain a required performance during the required service period by uniting the design and construction with the maintenance, and synchronizing, was proposed. In that case, the importance of setting the allowed reliability limit was pointed out.(2) For the monitoring of corrosion by the polarization resistance, and estimation of deterioration and the performance, RC beams were subjected to salt water condition. Loading tests were performed both before and after deterioration, and then weight of corroded reinforcing bar was measure.(3) There are still a lot of uncertain points concerning the loading capacity of concrete members with deterioration due to ASR, under reversed cyclic loading. Then, the reversed cyclic loading tests were performed on RC beams with ASR deterioration.(4) It is important to evaluate the effect of scatter and distribution of concrete strength for the reliability analysis of existing concrete structures. In this study, loading tests of RC beams considering distribution of concrete strength were performed. And also FEM analyses were performed for comparison with the experimental results.(5) The uncertainty of some parameters of the RC bridge with chloride induced deterioration was investigated referring to the result of the research of the deterioration mechanism, and the performance evaluation of a structure was performed. Moreover, a bridge structure constituted by several girders has degradation in girder stiffness due to corrosion of reinforcing bars and cyclic loading. The safety evaluation of such bridges considering scatter of section force due to degradation in girder stiffness, was also performed.