The Mechanics Principle And Experimental Research Of The New "Release-Prevent" Composite Reinforced Structure

In the paper the advantages and disadvantages of traditional reinforced concrete (RC) structures are summarized in brief, and the developing history and research status of application of FRP material to RC structures introduced.Based on the previous achievements of the research team, three mechanical mechanisms are generalized for the GFRP composite RC beams according to the fracture mechanics in the paper, and the interface problem of the new structure preliminarily analyzed. The simplified model for the new composite RC beam was built with finite elements to provide a new analytical approach. To further explore the mechanical behavior of the new composite RC beam and promote its future engineering application, a number of specimen beams of big dimensions (4000mm×180mm×450mm) have been tested in flexure, the excellent mechanical properties of the new beam verified and the design idea combining'release'with'prevent'checked. The experimental results indicate that, in the new composite RC beam the advantages of each material can be fully exploited to give much higher bearing capacity than common RC beams, at the same time the crack distribution as well as the post-cracking rigidity of the new beam greatly improved. The experimental research of the structure design idea combining'release'with'prevent'proved the remarkable increase of the new beam's ultimate bearing capacity, the improvement of the new beam's post-cracking rigidity and anti-deflection properties due to closure of the cracks, and the enhancement of anti-crack performance which is shown by the smaller crack widths under the same load levels and the tiny development of the cracks after they have been closed at their lower openings. In addition, the calculating formula of the ultimate bearing capacity for the new beam with the design idea combining'release'with'prevent'is deduced in the paper.