The HILTI catalogue specifies using a fixture hole diamater "dh" for each anchor diameter. Would it be ok to use a hole larger (Oversized hole) than the specified "dh"?
Jelean,
In regards to your quesitons:
(1) No, there are no tolerance limits for the fixture hole diameter. Hilti will provide the minimum required; however, the hole can be larger, but it will be up to the design engineer to verify the shear bearing area, as discussed previously.
(2) Pre-set is the installation process where the anchor is installed prior to the fixture plate being place on the concrete surface, while through set is the process where the anchor is installed into the base material while the fixture is resting on the surface of the base material.
Let us know if you have any other questions.
Regards,
Bryan
Jelean,
As you have noticed, the fixture hole size (d_fixture) is provided to ensure that the anchor can be properly installed in either a pre-set or through set condition. If a larger fixture hole is to be used, it would be up the design engineer to verify how the oversized fixture hole will transfer the shear. One common approach by designers is the use of larger diameter washers to increase the shear bearing area.
Let us know if you have any additional questions.
Regards,
Bryan