中文摘要：

民国时期钢筋混凝土结构使用年代较长，一般已超过合理使用年限，有不同程度的损伤，迫切需要加固修缮。但由于其大多为文物建筑或保护性历史建筑，承载着一些历史信息与文化价值，对其加固修缮应在充分保存历史信息的前提下合理进行结构性能和耐久性的提升。为了科学化、规范化地保护民国钢筋混凝土建筑，通过对典型案例的现场检测和调研，对这类建筑的常见缺陷进行分析和总结，结合保护原则，分别对混凝土柱、混凝土梁和混凝土板提出针对不同损伤程度的适宜性加固修缮方法。

英文摘要：

In China, the reinforced concrete buildings built during the period of the Republic of China have been used for so long a time that they now have different levels of damages and need to be strengthened and repaired ur- gently. Because most of these buildings are landmarks or protected historic buildings that bear historical information and culture value, they should be strengthened with preservation of historical information. In order to scientifically preserve these buildings, some typical cases were tested and investigated on site. The common defects of these buildings were analyzed, and the strengthening methods for different defects of concrete columns, beams and slabs were developed based on the analysis of common defects and preservation principles.