Ultimate Stress of Prestressing Steel in Prestressed Concrete Beams Strengthened by External Prestressing

외부 프리스트레싱으로 보강된 프리스트레스트 콘크리트 보에서 프리스트레싱 강재의 극한응력

Park Sang-Yeol

  • Published : 2004.10.01


This study deals with literature review, developing a predicting equation for the ultimate stress of internal and external prestressing steel, and an experimental test with the parameters affecting the ultimate stress of prestressing steel in prestressed concrete beams strengthened by external prestressing tendons. The proposed predicting equation takes rationally the effect of internal and external prestressing steels into consideration as a function of prestressing steel depth to neutral depth ratio. In the experimental study, prestressed concrete beams strengthened using external steel tendons are tested with the test parameters having a large effect on the ultimate stress of internal and external prestressing steel. The test parameters include internal and external prestressing steel reinforcement ratio and span to depth ratio. The test results are analyzed to confirm the rationality and applicability of the proposed equation for predicting the ultimate stress of internal and external prestressing steel. This research shows that the results obtained by the proposed equation for predicting the ultimate stress agreed very well with the test results.


external prestressing;ultimate stress;strengthening;unbonded;predicting equation


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