Repair and rehabilitation of composite pipes

9 Shear stress distribution along various joint lengths. 

In this section of the chapter, the basics of pipe repair techniques using FRP materials will be discussed. Design equations for selecting the appropriate thickness of FRPC repair wrap will be provided. Various commercially available repair kits will be introduced. The advantages and specific attributes of the various repair techniques will also be discussed. 

Nowadays, the use of FRP materials instead of the traditionally used steel sleeves for repair and rehabilitation of pipes has become quite popular. The most commonly used FRP pipeline repair materials consist of fibers such as glass and carbon, whereas the most commonly used resin is epoxy. FRP, with a combination of glass fibers and epoxy resin, is mostly used in the pipeline industry due to the following characteristics  

Excellent corrosion resistance Fligh strength-to-weight ratio Light weight compared to most metals Non-conductive to electricity Dimensional stability Low maintenance cost Unlimited shape/size configurations 

Orthotropic in nature (different properties in different directions) Relatively lower material cost (in comparison to carbon). 

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