STRUCTURAL PERFORMANCE OF PC BRIDGE REMARKABLY
DAMAGED BY CHLORIDE INDUCED CORROSION AND
STRENGTHENING EFFECTS OF EXTERNAL CABLE METHOD
32nd Our World in Concrete and Structures (OWICs) - 2007
T. Amino*, TOA Corporation, Japan
A. Moriwake, TOA Corporation, Japan
T. Habuchi, TOA Corporation, Japan
chloride attack, structural performance, PC Bridge, external cable method
When RC or PC structures are built in coastal and offshore areas, various damages
due to chloride attack appear on the surface of concrete structures relatively quickly.
Therefore, in the maintenance of marine concrete structures, it is very important to
evaluate the relationship between the degradation of structural performance and the
state of damages adequately in order to conduct the appropriate maintenance work for deterioration situations of the structures. However, in the present state, it is extremely difficult to determine this relationship from the results of investigation, and it has been hoped to establish the method to judge the necessity of strengthening considering a balance between the risks of structural degradation and the investment in maintenance.
In this paper, the results of loading test using the real road bridge, which was
removed at 26-years after construction by chloride induced deterioration, was described. As a result, it could be found that the structural performance degradation of PC girder, whose PC cables were severed due to corrosion at the center of span, was influenced by the number of PC cables severed. Moreover, the actual bending crack initiated load was almost consistent with the calculation in case of not considering PC cables severed. In addition, the strengthening effects of the external cable method were examined by using the above mentioned PC girder, in order to figure out the optimum tensioning force of external cables considering the progress of future deterioration of PC girder investigated