Grooving Method to Postpone Debonding of FRP Sheets Used for Shear Strengthening

One of the most common practices for strengthening the reinforced concrete structures is the application of FRP (Fiber Reinforce Plastic) sheets to increase the flexural and shear strengths of the member. The elastic modulus of FRP is considerably higher than that of concrete. This will result in debonding between the FRP sheets and concrete surface. With conventional surface preparation of concrete, the ultimate capacity of the FRP sheets can hardly be achieved. New methods for preparation of the bonding surface have shown improvements in reducing the premature debonding of FRP sheets from concrete surface. The present experimental study focuses on the application of grooving method to postpone debonding of the FRP sheets attached to the side faces of concrete beams for shear strengthening. Comparison has also been made with conventional surface preparation method. This study clearly shows the efficiency of grooving method compared to surface preparation method, in preventing the debonding phenomenon and in increasing the load carrying capacity of FRP.

Authors:

• Davood Mostofinejad
• Seyed Amirali Mostafavizadeh
• Amirhomayoon Tabatabaei Kashani

Keywords:

• FRP composite
• grooving
• rehabilitation
• reinforced concrete
• shear strengthening
• surface preparation.

References:

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