Different from traditional strengthening methods, the technology on replacement of structural members is a new strengthening concept for solving the problem of local failures in prestressed concrete cable-stayed bridges. To clarify the characteristics and realization ways of this technology, practical experience and latest achievements of strengthening prestressed concrete cable-stayed bridges in recent years in China were summarized comprehensively, such as replacement of stay cables, replacement of closure segment, replacement of tension rocker bearing cables at subsidiary piers, et al. Forms of Special diseases were described, and their failure mechanisms were given. Then calculation methods and key techniques of these strengthening ways were introduced. Engineering application and practice showed, the technology on replacement of structural members is a system engineering, namely, not only new structural members should meet the mechanical requirements of their own, but also the structural condition of whole bridge should be improved through replacing structural members. Establishment and development of this technology had important and far-reaching significance to promote the technical level of strengthening long-span bridges under the condition of special diseases and ensure bridges in the sate of safe and sustainable operation.
