Hi. We're developing a design to attach posts to existing RC concrete. There is a desire to use the HUS4 screw anchor without resin. There will be very little flexibility on the position of the drill holes, so there is a risk of clashing with rebar in the concrete, in which case we will drill/core through the rebar. As the HUS4 will need to bite into the side of the drill hole, do you foresee any problems if the side of the drill hole contains steel from rebar? Could this damage the screw or reduce its reliability?
Thanks for your question. If reinforcement is hit during the drilling process, then the installer should check with the responsible engineer as to what action is to be taken. If the engineer does not approve drilling through the reinforcement,
then the anchor should be moved. No attempts should be made to enlarge the drill hole diameter of force the drill or screw anchor past the rebar as this will result in a hole/ anchor that is no longer straight. If rebar is suspected to be in the proposed area, it may well be beneficial to scan the area to locate the bars using a simple scanning device such as the HILTI PS50, PS85 and simply mark the surface of the concrete to avoid a clash.
Regarding reuse of the HUS4 it can be removed and reused in a new hole. Between each reuse the wear of the screw must be checked with the corresponding HRG tube . Where there are obvious signs of damage to the screw it should not be used.