Translated Title
Experimental study on the extant pre-stressed force in 20-year old prestressed structure
Translated Abstract
In order to study the extant pre?stressed force in the pre?stressed concrete beam, the stress?releasing meth?od on the pre?stressed hollow slab beam which had served for 20 years was used in the grooving test. The effects of different cutting positions and cutting gap spacing on the testing stress release rate are researched. The variation law of the release concrete working stress with the changing of the notch depth and gap spacing in the grooving test was ana?lyzed, achieving the depth of notch when the working stress of beam concrete was release completely. The fitting func?tion between the cutting depth and the measured residual stress was established using numerical analysis software, so as to deduce the surface initial stress of the beam bottom. According to the derived formula of existing pre?stress of concrete, the initial stress generated from the derivation was substituted into the calculation formula, so as to get ex?tant pre?stress of the beam. By this method the extant pre?stressed force of beam was accurately estimated. This paper provided reference to a certain extent for effective pre?stress evaluation and assessment of bridge structure.
Translated Keyword
extant pre-stressed force
fitting function
grooving method
in-service pre-stressed simply supported beam
stress-releasing
Access Number
WF:perioarticalhebgcdxxb201410004
