Shear Strengthening of RC T-Beams Using Mechanically Anchored Unbonded Dry Carbon Fiber Sheets

This research studies the feasibility and effectiveness of a new method of strengthening existing RC T-beams in shear by using mechanically anchored unbonded dry carbon fiber (CF) sheets. This method eliminates the debonding of epoxy-bonded carbon-fiber-reinforced polymer (CFRP) sheets and utilizes the full capacity of dry CF sheets. In this method, dry CF sheets are wrapped around and bonded to 2 steel rods. The rods are then anchored to the corners of the web-flange intersection of the T-beam with mechanical bolts. This makes a U-shaped dry CF jacket around the web which increases the shear strength of the T-beam using the privilege of higher tensile strength and modulus of elasticity of dry CF compared to composite CFRP. Three RC T-beams with shear span-to-depth ratio of 2.0 were tested under increasing monotonic load until failure. The pilot tests were done as a proof-of-concept of the effectiveness of the proposed method in increasing the shear capacity of the RC T-beams. The first T-beam, which was tested as the control beam, failed in shear. The second beam was strengthened by using a U-shaped CFRP sheet that was externally bonded to the web of the beam in the shear zones. The third beam was strengthened by using an anchored U-shaped dry CF sheet. The test results showed that the beam strengthened by the new mechanically anchored dry CF had about 48% increase in shear capacity as compared to the control beam and 16% increase in shear capacity as compared to the beam strengthened by CFRP epoxy-bonding method.

  • Availability:
  • Supplemental Notes:
    • Abstract reprinted with permission from ASCE
  • Authors:
    • Galal, Khaled
    • Mofidi, Amir
  • Publication Date: 2010-1

Language

  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 01152130
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 5 2010 5:47PM