Title: Design Philosophy for Structural Strengthening with FRP

Author(s): Paul L. Kelley, Michael L. Brainerd, and Milan Vatovec

Publication: Concrete International

Volume: 22

Issue: 2

Appears on pages(s): 77-82

Keywords: ductility; materials tests; plastics; polymers and resins; reinforcing materials; reliability; strengthening; structural design

DOI:

Date: 2/1/2000

Abstract:
The article discusses several key issues related to the methodology for the design of post-strengthening of concrete structures using FRP. The basic design philosophy presented here aligns with and expands upon the guidelines being currently considered by ACI Committee 440 F. Several design/philosophy issues that FRP-strengthening designers must consider are: Minimum required pre-strengthened strength (strength of the unstrengthened element) criterion to prevent collapse if the FRP is compromised due to uncontrollable events (fire, vandalism, impact, etc.); limits on strength enhancement to maintain ductile behavior; appropriate reliability factors and limits on design strength; and condition of the concrete substrate. Designers should also consider that standard test procedures for FRP systems are emerging. Care should be used while interpreting material data, and substitution of untested system components should be avoided.