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SP-215 The field application of fiber-reinforced polymer (FRP) composite materials as reinforcement for concrete structures has been growing rapidly in recent years, mostly with interest in alternatives to steel reinforcing bars and for strengthening concrete structures. FRP products provide options and benefits not available using traditional materials. As a result of the extensive use of FRP as internal and external reinforcement for new structures and strengthening concrete structures, respectively, ACI Committee 440 organized three technical sessions on “Field Application of FRP Reinforcement—Case Studies” with a total of 21 papers presented at the ACI Fall 2003 Convention in Boston, Mass. All papers deal with case studies and demonstration projects to provide clear evidence of the practicality, credibility, and maturity attained by this technology. This volume includes the papers presented during the Fall 2003 Convention, plus five additional papers that augment the range of field applications and case studies. The goal of this document is to help practitioners implement FRP technology, while providing testimony that design and construction with FRP material systems is rapidly moving from emerging to mainstream technology.

In 1997, a precast, prestressed T-beam in the Ala Moana Shopping Center parking garage, in Honolulu, Hawaii, was strengthened in flexure using carbon fiber reinforced polymer (CFRP) strips epoxy bonded to the soffit of the beam. When the parking garage was demolished in June 2000, this beam and two control beams were salvaged and brought to the University of Hawaii for testing. This paper presents the retrofit procedures used during field application of the CFRP strips. It also describes the beam recovery and preparation for laboratory testing. The test program and results of the flexural testing of both unstrengthened and strengthened beams under four-point loading are presented in detail. The CFRP retrofit significantly increased the flexural capacity of the beam while also increasing its flexural ductility. The failure moment was well in excess of the nominal moment capacity predicted using the strain-compatibility procedure described in the ACI 440R-02 report.

To prevent future blowouts of sections of the 50-year-old pipe, the Providence Water Supply Board decided to evaluate the condition of a main water pipeline. Non-destructive testing (NDT) investigations revealed that certain sections of the pipe were potentially deficient due to corrosion and breakage of the prestressing system. Strengthening of deficient sections was necessary to maintain the pipeline operational. A carbon fiber in-situ lining appeared to be the fastest, least disruptive, and most cost-effective upgrade solution. The specialty concrete repair contractor conducted full-scale tests to validate optimum FRP repair and waterstop termination design. In these tests, after the carbon fiber liner was installed, the prestressing strands of the FRPstrengthened section were cut leaving the FRP to be the only reinforcement. The test pipe was progressively pressurized until failure occurred at approximately 2-1/2 times the pipe service and surge pressures. The full-scale test proved the integrity of the system beyond theoretical prediction and assured the owner that strength was added to the pipe sections. The lightweight, flexible carbon fiber material along with thorough planning helped overcome challenging working conditions and provided a fast and effective upgrade solution.

Use of ACM in the form of FRP laminates in rehabilitation of concrete structures is the prime application of ACM in Egypt. FRP laminates are applied for strengthening reinforced concrete slabs or beams in flexure and shear as well as for confinement of reinforced concrete columns. This paper briefly introduces selected projects to demonstrate the current practice of FRP in Egypt. In the first application, carbon FRP (CFRP) laminates in the form of strips and sheets were applied to strengthen a public building suffering from differential settlement of the foundation. In a different application, CFRP laminates were used to upgrade a residential building to be used for commercial purpose. The paper summarizes the design aspects, construction details and recommendations for future application of ACM.

The Gentilly-1 nuclear power plant, in Quebec, Canada, was decommissioned in 1978. Since that time, the containment structure has been used for the storage of the moderately contaminated nuclear reactor. The enforcement of more rigorous environmental regulations, as well as economic considerations, have raised the decommissioning period from 40 to 100 years, thus severely increasing the durability requirements for the structure. The containment structure, constructed of thick prestressed concrete, was in good condition except for the secondary concrete. The latter is a keystone for the durability of the structure because it fills the recesses and protects the terminations of the tendons against corrosion. The differential shrinkage caused cracking and debonding and, with freeze-thaw cycling over the years, the secondary concrete had to be removed and replaced. The ringbeam, at the top of the containment structure, was severely affected because the numerous tendons of the roof terminate at that level. The retrofit of the ring-beam consisted of replacing the secondary concrete with highquality shrinkage-compensated mortar and concrete, followed by FRP wrapping. The layout of the FRP wrap was designed to mitigate the adverse effects of the new secondary concrete shrinking-induced cracks. Most of the concrete cold joints were covered by the FRP wrap, which was anchored on the dome roof to provide an effective support.