The Detection, Evaluation And Improvement Of Perstressed Concrete Cable-Stayed Bridge

Cable-stayed bridges have been rapidly developed in past decades. The main load-bearing components are the main towers, main beam and cables that may be considered as external prestressing tender. High redundancy and flexibility are the characteristics of the structure. The main beam and cable's changes of stress are more complex under all kinds of load, and can be affected by geometric nonlinearity. The durability of the cable-stayed bridge and especially the corrosion protection of the cable haven't been solved yet, as many cable-stayed bridges have to renew all cables for corrosion. The corrosion and vibrating fatigue of the cables have been challenge and threaten of the cable-stayed bridges both in use and in development. The concrete components of the structure easily crack under complex loads, and which will in return affects the durability of the components. Whether the affiliated facilities such as drainage system of the deck, expansion joint and support abutment are in good use or not and the deck is cleaning or not can also affects the whole structure's serviceability and load bearing capacity. According to all kinds of defects of the cable-stayed bridges we should do more detection and maintenance to ensure the serviceability and load bearing capacity, to maintain the durability of the structure, to prevent little defect developing into large disaster, and to low the fee of long-term maintenance. This thesis analyzes the condition and reasons of the defects from the aspect of practice, and introduces the works of defects detecting, load test on real bridge, maintenance and consolidation. Also two instances of cable-stayed bridge defects disposal are given out to introduce the development of actual state.