Experimental Investigation on the Effect of Bond Thickness on the Interface Behaviour of Fibre Reinforced Polymer Sheet Bonded to Timber

The bond mechanism between timber and fibre
reinforced polymer (FRP) is relatively complex and is influenced by
a number of variables including bond thickness, bond width, bond
length, material properties, and geometries. This study investigates
the influence of bond thickness on the behaviour of interface, failure
mode, and bond strength of externally bonded FRP-to-timber
interface. In the present study, 106 single shear joint specimens have
been investigated. Experiment results showed that higher layers of
FRP increase the ultimate load carrying capacity of interface;
conversely, such increase led to decrease the slip of interface.
Moreover, samples with more layers of FRPs may fail in a brittle
manner without noticeable warning that collapse is imminent.

Authors:

• Abbas Vahedian
• Rijun Shrestha
• Keith Crews

Keywords:

• FRP
• single shear test
• bond thickness
• bond strength.

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