What is α5 in the anchorage length of splices equation for the embedment depth lb refer to, as I can see that in the definition it says it takes into account the confinement by transverse pressure. Can you please explain further what does transverse pressure mean?
TIA
Hi Tasneem
Thank you for contacting Hilti.
The a5 factor takes into account the effect of the pressure transverse to the plane of splitting along the design
anchorage length. Please refer to EN 1992-1: 8.4.4 for the details of this coefficient. This effect is also considered and further defined in TR 069 section 4.4 with Ktr when discussing bond splitting behaviour.
Basically this factor will include the effect of cross-sectional stress within existing member created by its existing reinforcement which is in a plane perpendicular to post-installed rebar. This information can be provided from the structural designer and then incorporated into the design.
Hope the above explanation has answered your query.
Regards,
Amad