Structural concrete and steel adherends in civil infrastructure

4 Structural concrete and steel adherends in civil infrastructure 

b) Lap-shear stress distribution along bondlength for identical double-strap CFRP/steel plate specimens having different CF moduli (Al-Shawaf, 2010). 

Consequently, the characteristic failure mode(s) for external FRP/concrete composite joints can be referred to as adherend/concrete-based. 

On the other hand, the situation is more complicated in the case of steel adherends where several possible failure modes at different locations in the adhesive joint can be expected (Haghani et aL, 2009). In order to acquire clear understanding of the behavioural differences in terms of stress between concrete and steel adherends, likely failure modes for a CFRP/steel plate double-strap configuration are presented in Fig. 10.5. Assuming optimum surface preparation procedures, triggering failure for all modes depicted in Fig. 10.5(a)-(d) can be attributed as adhesive/matrix-based. The only exception 

It can be implied, from the above discussion, that failure initiation and propagation mechanisms for similar configurations, adhesives and reinforcing fibres of adhesively bonded CFRP to concrete and steel adherends are ntterly different, and are substantially influenced by the mechanical and microstructural properties for each adherend. 

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