Effect of Uneven Adhesive Layer on Interfacial Stress of Beams Strengthened with CFRP Plate

DU Yunxing, HOU Chunxu, ZHOU Fen

Abstract

Numerical modeling method was adopted to investigate the stress of uneven adhesive layer and the interfacial stresses of the beam strengthened by CFRP plate. The notch was set on the interface of strengthened beam to change the local thickness of adhesive layer. Six cases were set up according to the depth, width and location of the notch. The analysis results indicate that the peak interfacial stresses are much greater than beam without the notch when the notch is located at a short distance from the plate end. When the notch is far from the plate end, the peak interfacial stresses are barely been influenced. The peak interfacial shear and normal stresses reach the maximum values when the notch is located at around 0.83% and 1.25% of the FRP length from the plate end, respectively. With the increase of the length or depth of the notch, interfacial shear and normal stresses increase simultaneously. Both interfacial shear and normal stresses are more sensitive to the change of depth than change of length. The stress distribution of adhesive layer along the thickness-wise direction is uniform except the CFRP plate-end area. When the notch is located at the plate-end area, the notch leads to a stronger variation of stresses of adhesive layer at the plate-end area and also a more non-uniform stress distribution within the notch-area along the thickness-wise direction.

 

 

Keywords: CFRP,  notches,  finite element analysis,  interfacial stress,  stress distribution


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References


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