Hello, we are designing a post fixed slab to slab connection detail. We performed the design with both Hilti Anchor and Rebar and we are getting a considerable difference to the required embedment depth comparing the results. We have checked all the inputs and we believe that they are the same. Are we missing something in relation to the way that the two software
perform the design checks? This difference to the embedment depth is a bit worrying...Thank you
Thank you for your enquiry. Ok Simply put you are comparing different design approaches. Profis Rebar is following the Eurocode as though the bar was originally cast-in with the resin using the same bond strength criteria. In effect the post installed rebar 'clamps' the existing and new concrete together with any shear load taken up through friction acting over the interface surface. It is therefore reaching an equilibrium with local or global concrete struts. Profis Engineering is following anchor theory where the 'anchor' resists the tension ,shear or a combination of both and if using a resin anchor utilises a higher bond strength using the tensile strength of the concrete. Subsequently the modes of failure are also different between between the two design approaches. If you search the askhilti section you will find webinars and presentations relating to the individual approaches.